For reactions to occur, the particles of the reactants must collide. The fewer the collisions that take place, the slower the rate of a reaction. Which DECREASES the frequency of collision between reactant particles? [rr-1]
For reactions involving gaseous reactants, decrease the pressure of the gases
For reactions involving solutions, raise the concentration of the solution
If a solid is reacting with a liquid, break the solid into smaller pieces
Raise the temperature of the reaction mixture
For reactions to occur, the particles of the reactants must collide. The fewer the collisions that take place, the slower the rate of reaction. Which DECREASES the frequency of collision between reactant particles? [rr-2]
For reactions involving gaseous reactants, increase the pressure of the gases
For reactions involving solutions, decrease the concentration of the solution
If a solid is reacting with a liquid, break the solid into smaller pieces
Raise the temperature of the reaction mixture
For reactions to occur, the particles of the reactants must collide. The fewer the collisions that take place, the slower the rate of reaction. Which INCREASES the frequency of collision between reactant particles? [rr-3]
For reactions involving gaseous reactants, decrease the pressure of the gases
For reactions involving solutions, decrease the concentration of the solution
If a solid is reacting with a liquid, break the solid into smaller pieces
Lower the temperature of the reaction mixture
For reactions to occur, the particles of the reactants must collide. The fewer the collisions that take place, the slower the rate of reaction. Which INCREASES the frequency of collision between reactant particles? [rr-4]
For reactions involving gaseous reactants, decrease the pressure of the gases
For reactions involving solutions, decrease the concentration of the solution
If a solid is reacting with a liquid, use large pieces of the solid
Increase the temperature of the reaction mixture
Calcium carbonate in the form of limestone dissolves in hydrochloric acid and giving off carbon dioxide gas. Which conditions would produce the fastest reaction? [rr-5]
temperature of 40°C and 10cm3 of dilute acid
temperature of 20°C and 10cm3 of dilute acid
temperature of 40°C and 5cm3 of dilute acid and 5cm3 of water
temperature of 20°C and 5cm3 of dilute acid and 5cm3 of water
Calcium carbonate in the form of limestone dissolves in hydrochloric acid and giving off carbon dioxide gas. Which conditions would produce the slowest reaction? [rr-6]
temperature of 40°C and 10cm3 of dilute acid
temperature of 20°C and 10cm3 of dilute acid
temperature of 40°C and 5cm3 of dilute acid and 5cm3 of water
temperature of 20°C and 5cm3 of dilute acid and 5cm3 of water
Iron reacts with hydrochloric acid to form iron(II) chloride and hydrogen gas. 2g of iron is added to 100cm3 of dilute hydrochloric acid. Which conditions produces the fastest reaction? [rr-7]
iron pieces at 25°C
iron pieces at 50°C
iron powder at 25°C
iron powder at 50°C
Iron reacts with hydrochloric acid to form iron(II) chloride and hydrogen gas. 2g of iron is added to 100cm3 of dilute hydrochloric acid. Which conditions produces the slowest reaction? [rr-8]
iron pieces at 25°C
iron pieces at 50°C
iron powder at 25°C
iron powder at 50°C
A group of students carried out an experiment in which they added manganese dioxide to rapidly decompose a solution of hydrogen peroxide. To show that the manganese dioxide was acting as a catalyst, what must they do before and after the experiment? [rr-9]
BEFORE: weigh the hydrogen peroxide solution and manganese dioxide in separate containers before mixing AFTER: weigh both of the containers again
BEFORE: weigh the hydrogen peroxide solution in a beaker and then add the manganese dioxide to the beaker AFTER: weigh the beaker and its contents
BEFORE: weigh the manganese dioxide and then add the hydrogen peroxide solution to the beaker AFTER: weigh the beaker and its contents
BEFORE: weigh the manganese dioxide and a dry filter paper AFTER: filter the solution, dry the filter paper and the solid residue, weigh the filter paper
When marble chips dissolve in acid, the reaction can be speeded up by? [rr-10]
grinding the marble chips
lowering the temperature
using a larger flask
using more dilute acid
When marble chips dissolve in acid, the reaction can be slowed down by? [rr-11]
grinding the marble chips
lowering the temperature
using a larger flask
using more dilute acid
Copper(II) oxide catalyses the decomposition of hydrogen peroxide to form oxygen. In acting as a catalyst the copper(II) oxide? [rr-12]
causes the decomposition to begin
increases the total amount of oxygen formed
increases the rate at which oxygen is formed
prevents the decomposition of the oxygen formed
Which mixture will enable the fastest reaction to take place between solid calcium carbonate (marble chips) and dilute hydrochloric acid? [rr-13]
large chips, concentrated acid, low temperature
low temperature, small chips, dilute acid
concentrated acid, high temperature, small chips
high temperature, small chips, dilute acid
Which mixture will produce the slowest reaction to take place between solid calcium carbonate (marble chips) and dilute hydrochloric acid? [rr-14]
large chips, concentrated acid, low temperature
low temperature,
large chips, dilute acid
concentrated acid, high temperature, small chips
high temperature, small chips, dilute acid
Platinum catalyses the reaction between
sulfur dioxide SO2 and oxygen O2 to form sulfur trioxide SO3. Which of the statements 1, 2 or 3 is/are correct? [rr-15] 1. more
sulfur trioxide is formed when more catalyst is used 2. the catalyst increases the rate of reaction between
sulfur dioxide and oxygen 3. when the reaction is complete the platinum catalyst has not lost any mass
1 and 2
1 and 3
2 and 3
1, 2 and 3
Platinum catalyses the reaction between
sulfur dioxide SO2 and oxygen O2 to form sulfur trioxide SO3. Which statement(s) 1, 2 or 3 is NOT correct? [rr-16] 1. less
sulfur trioxide is formed when more catalyst is used 2. the catalyst decreases the rate of reaction between
sulfur dioxide and oxygen 3. when the reaction is complete the platinum catalyst has gained mass
only 1
only 1 and 3
only 2 and 3
1, 2 and 3
The rate of reaction between acid and marble chips can be decreased by? [rr-17]
warming
stirring
using larger chips
using more acid
A small quantity of marble chips is added to a large excess acid. Carbon dioxide gas is formed. Which will double the amount of carbon dioxide formed? [rr-18]
mass of acid
mass of marble chips
mass of water
volume of acid
Limestone reacts with hydrochloric acid to produce carbon dioxide. A student set up four experiments A to D. Which experiment would you expect to go the fastest? [rr-19]
limestone powder, dilute acid at 20°C
limestone lumps, dilute acid at 40°C
limestone lumps, concentrated acid at 20°C
limestone powder, concentrated acid at 40°C
Limestone reacts with hydrochloric acid to produce carbon dioxide. A student set up four experiments A to D. Which experiment would you expect to go the slowest? [rr-20]
limestone powder, dilute acid at 20°C
limestone lumps, dilute acid at 20°C
limestone lumps, concentrated acid at 40°C
limestone powder, concentrated acid at 40°C
A small quantity of calcium carbonate is added to a large excess acid. Carbon dioxide gas is formed. Which of the following will halve the amount of carbon dioxide formed? [rr-21]
doubling the temperature of the acid
doubling the volume of acid
halving the mass of the acid
halving the mass of the calcium carbonate
Sodium thiosulfate solution reacts with hydrochloric acid to form sodium chloride,
sulfur dioxide, sulfur and water. The reaction can be followed by measuring the time it takes for enough of the
sulfur precipitate to form to obscure a black cross marked on white paper. Which will decrease the time it takes for the black cross to disappear? [rr-22]
increase the concentration of the hydrochloric acid
decrease the concentration of the sodium thiosulfate
cool the mixture
add more water to the mixture
Sodium thiosulfate solution reacts with hydrochloric acid to form sodium chloride,
sulfur dioxide, sulfur and water. The reaction can be followed by measuring the time it takes for enough of the
sulfur precipitate to form to obscure a black cross marked on white paper. Which will decrease the time it takes for the black cross to disappear? [rr-23]
decrease the concentration of the hydrochloric acid
increase the concentration of the sodium thiosulfate
cool the mixture
add more water to the mixture
Sodium thiosulfate solution reacts with hydrochloric acid to form sodium chloride,
sulfur dioxide, sulfur and water. The reaction can be followed by measuring the time it takes for enough of the
sulfur precipitate to form to obscure a black cross marked on white paper. Which will decrease the time it takes for the black cross to disappear? [rr-24]
decrease the concentration of the hydrochloric acid
decrease the concentration of the sodium thiosulfate
heat the mixture
add more water to the mixture
An experiment was carried out at a temperature of 25oC by dissolving 0.2g of small limestone granules into 30cm3 of hydrochloric acid. The acid concentration was 1.0 mol/dm3 and in excess so all the limestone dissolved. The reaction was followed by measuring the volume of carbon dioxide given off over a period of 6 minutes. A 2nd experiment was done in an identical manner but using 0.2g of limestone lumps. Which of the graphs W, X, Y or Z might you expect for the results? [rr-25]
graph line W
graph line X
graph line Y
graph line Z
An experiment was carried out at a temperature of 25oC by dissolving 0.2g of small limestone granules into 30cm3 of hydrochloric acid. The acid concentration was 1.0 mol/dm3 and in excess so all the limestone dissolved. The reaction was followed by measuring the volume of carbon dioxide given off over a period of 6 minutes. A 2nd experiment was done in an identical manner but using 0.4g of the same limestone granules. Which of the graphs W, X, Y or Z might you expect for the results? [rr-26]
graph line W
graph line X
graph line Y
graph line Z
An experiment was carried out at a temperature of 25oC by dissolving 0.2g of small limestone granules into 30cm3 of hydrochloric acid. The acid concentration was 1.0 mol/dm3 and in excess so all the limestone dissolved. The reaction was followed by measuring the volume of carbon dioxide given off over a period of 6 minutes. A 2nd experiment was done in an identical manner but using acid of 2.0mol/dm3 concentration. Which of the graphs W, X, Y or Z might you expect for the results? [rr-27]
graph line W
graph line X
graph line Y
graph line Z
An experiment was carried out at a temperature of 25oC by dissolving 0.2g of small limestone granules into 30cm3 of hydrochloric acid. The acid concentration was 1.0 mol/dm3 and in excess so all the limestone dissolved. The reaction was followed by measuring the volume of carbon dioxide given off over a period of 6 minutes. A 2nd experiment was done in an identical manner but using 0.1g of the same limestone granules. Which of the graphs W, X, Y or Z might you expect for the results? [rr-28]
graph line W
graph line X
graph line Y
graph line Z
An experiment was carried out at a temperature of 25oC by dissolving 0.2g of small limestone granules into 30cm3 of hydrochloric acid. The acid concentration was 1.0 mol/dm3 and in excess so all the limestone dissolved. The reaction was followed by measuring the volume of carbon dioxide given off over a period of 6 minutes. A 2nd experiment was done in an identical manner but at a temperature of 50oC. Which of the graphs W, X, Y or Z might you expect for the results? [rr-29]
graph line W
graph line X
graph line Y
graph line Z
An experiment was carried out at a temperature of 25oC by dissolving 0.2g of small limestone granules into 30cm3 of hydrochloric acid. The acid concentration was 1.0 mol/dm3 and in excess so all the limestone dissolved. The reaction was followed by measuring the volume of carbon dioxide given off over a period of 6 minutes. A 2nd experiment was done in an identical manner but using acid of 0.5mol/dm3 concentration. Which of the graphs W, X, Y or Z might you expect for the results? [rr-30]
graph line W
graph line X
graph line Y
graph line Z
Which will react the fastest with hydrochloric acid? [rr-31]
marble chips at 40oC
marble chips at 25oC
powdered marble at 40oC
powdered marble at 25oC
Which will react the slowest with hydrochloric acid? [rr-32]
marble chips at 40oC
marble chips at 25oC
powdered marble at 40oC
powdered marble at 25oC
An acid reacts with some tablets. The rate of reaction is decreased by? [rr-33]
cooling the tablets and the acid
crushing the tablets before adding the acid
stirring the tablets in the acid
using a more concentrated acid
A catalyst can increase the rate of a chemical reaction. Which of the following is also TRUE about catalysts? [rr-34]
their appearance is unchanged at the end of the reaction
they have to be a metal
they have to be a solid
they are chemically the same at the end of the reaction
A large amount of calcium carbonate (excess) is added to a small amount of dilute hydrochloric acid. Which will double the volume of carbon dioxide finally formed? [rr-35]
doubling the mass of calcium carbonate
doubling the volume of the hydrochloric acid
halving the mass of the hydrochloric acid
doubling the temperature
A large amount of calcium carbonate (excess) is added to a small amount of dilute hydrochloric acid. Which will double the volume of carbon dioxide finally formed? [rr-36]
doubling the mass of calcium carbonate
halving the volume of the hydrochloric acid
doubling the temperature
doubling the concentration of the acid
A large amount of calcium carbonate (excess) is added to a small amount of dilute hydrochloric acid. Which will halve the volume of carbon dioxide finally formed? [rr-37]
halving the mass of calcium carbonate
halving the volume of the hydrochloric acid
halving the temperature
doubling the concentration of the acid
A large amount of calcium carbonate (excess) is added to a small amount of dilute hydrochloric acid. Which will halve the volume of carbon dioxide finally formed? [rr-38]
doubling the mass of calcium carbonate
doubling the volume of the hydrochloric acid
halving the temperature
halving the concentration of the acid
Potatoes cook more quickly in boiling vegetable oil than in boiling water. This is because oil? [rr-39]
boils at a higher temperature than water
catalyses the cooking process
contains water
replaces the water in the potatoes
In a rates experiment the following carbon dioxide gas volumes were recorded by a student resulting from an acid-limestone reaction. The gas volume of CO2 formed at 1.5 min was omitted by accident.
time (min)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Vol (cm3)
0
8
15
?
26
30
33
36
38
39
40
40
40
What is the most likely value of the missing reading in cm3 of carbon dioxide? [rr-40]
18
21
23
24
In a rates experiment the following carbon dioxide gas volumes were recorded by a student resulting from an acid-limestone reaction.
time (min)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Vol (cm3)
0
8
15
21
26
30
33
36
38
39
40
40
40
At what time did the reaction stop? [rr-41]
4.5 min
6.0 min
5.0 min
5.5 min
In a rates experiment the following carbon dioxide gas volumes were recorded by a student resulting from an acid-limestone reaction.
time (min)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Vol (cm3)
0
8
15
21
26
30
33
36
38
39
40
40
40
At what approximate time is the speed of the reaction 8cm3gas/min? [rr-42]
2.0 to 2.5 min
0.0 t0 0.5 min
1.0 to 1.5 min
5.0 to 5.5 min
A gas was produced in a chemical reaction. The total volume of gas formed was measured at regular time intervals. Which graph would you expect the results to be like? [rr-43]
graph Q
graph W
graph Y
graph Z
Which is a chemical test for the gas hydrogen? [rr-44]
pops with lit splint
turns limewater cloudy
relights a glowing splint
bleaches damp litmus paper
Which is a chemical test for the gas carbon dioxide? [rr-45]
pops with a lit splint
turns limewater cloudy
relights a glowing splint
bleaches damp litmus paper
Which is a chemical test for the gas oxygen? [rr-46]
pops with a lit splint
turns limewater cloudy
relights a glowing splint
bleaches damp litmus paper
Which is a chemical test for the gas chlorine? [rr-47]
pops with a lit splint
turns limewater cloudy
relights a glowing splint
bleaches damp litmus paper
Which of the following gases is formed when a metal reacts with an acid? [rr-48]
hydrogen
carbon dioxide
oxygen
chlorine
Which of the following gases is formed when an acid reacts with a carbonate? [rr-49]
hydrogen
carbon dioxide
oxygen
chlorine
Which of the following is formed when a metal reacts with an acid? [rr-50]
O2
Cl2
H2
CO2
Which of the following is formed when a carbonate reacts with an acid? [rr-51]
O2
Cl2
H2
CO2
A solid was produced in a chemical reaction. The total mass of solid formed was measured at regular time intervals. Which graph would you expect the results to be like? [rr-52]
graph Y
graph W
graph Q
graph Z
A solid and a liquid reacted to produce a solution. The mass of the solid reactant was measured at regular time intervals. Which graph would you expect the results to be like? [rr-53]
graph W
graph Q
graph Y
graph Z
Two solids were heated and reacted to form another solid. The total mass of the solids was measured at regular time intervals. Which graph would you expect the results to be like? [rr-54]
graph W
graph Q
graph Y
graph Z
On mixing two reacting solutions a solid precipitate was formed. The mass of the solid precipitate was measured at regular time intervals. Which graph would you expect the results to be like? [rr-55]
graph W
graph Q
graph Y
graph Z
Limestone chips were reacted with acid in a beaker placed on a one pan electric balance. The mass of the reacting mixture was measured at regular time intervals. Which graph would you expect the results to be like? [rr-56]
graph W
graph Q
graph Y
graph Z
An experiment was carried out to dissolve small limestone granules into hydrochloric acid. Carbon dioxide gas is formed and was collected in a gas syringe. The initial results are marked as the 'original experiment'. The experiment was repeated after varying the reaction conditions (ie mass of limestone, size of limestone pieces, temperature or acid concentration). The speed of the reaction can be given in cm3/min, ie the speed at which carbon dioxide is formed. Which experiment is going at an approximate average speed of 30 cm3/min in the first half minute of the reaction? [rr-57]
graph line for experiment W
graph line for experiment X
graph line for experiment Y
graph line for experiment Z
An experiment was carried out to dissolve small limestone granules into hydrochloric acid. Carbon dioxide gas is formed and was collected in a gas syringe. The initial results are marked as the 'original experiment'. The experiment was repeated after varying the reaction conditions (ie mass of limestone, size of limestone pieces, temperature or acid concentration). The speed of the reaction can be given in cm3/min, ie the speed at which carbon dioxide is formed. Which experiment is going at an approximate average speed of 22 cm3/min in the first half minute of the reaction? [rr-58]
graph line for experiment W
graph line for experiment X
graph line for experiment Y
graph line for experiment Z
An experiment was carried out to dissolve small limestone granules into hydrochloric acid. Carbon dioxide gas is formed and was collected in a gas syringe. The initial results are marked as the 'original experiment'. The experiment was repeated after varying the reaction conditions (ie mass of limestone, size of limestone pieces, temperature or acid concentration). The speed of the reaction can be given in cm3/min, ie the speed at which carbon dioxide is formed. Which experiment is going at an approximate average speed of 6 cm3/min in the first minute of the reaction? [rr-59]
graph line for experiment W
graph line for experiment X
graph line for experiment Y
graph line for experiment Z
An experiment was carried out to dissolve small limestone granules into hydrochloric acid. Carbon dioxide gas is formed and was collected in a gas syringe. The initial results are marked as the 'original experiment'. The experiment was repeated after varying the reaction conditions (ie mass of limestone, size of limestone pieces, temperature or acid concentration). The speed of the reaction can be given in cm3/min, ie the speed at which carbon dioxide is formed. Which experiment is going at an approximate average speed of 3 cm3/min in the first minute of the reaction? [rr-60]
graph line for experiment W
graph line for experiment X
graph line for experiment Y
graph line for experiment Z
What would you increase, to increase the kinetic energy of particles involved in a chemical reaction? [rsa-1]
What would you decrease, to decrease the kinetic energy of particles involved in a chemical reaction? [rsa-2]
What must particles do with each other before they can react? [rsa-3]
What do you increase to make two gases react together faster at the same temperature? [rsa-4]
What do you decrease to make two gases react together more slowly at the same temperature? [rsa-5]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). Which of 1 to 5 is seen as the 'fizzing'? [rsa-6]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). Which of 1 to 5 is the 'salt' in the reaction? [rsa-7]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). Which of 1 to 5 has the formula HCl? [rsa-8]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). Which of 1 to 5 has the formula CaCO3? [rsa-9]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). Which of 1 to 5 has the formula CaCl2? [rsa-10]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). In what form would you add the marble to speed up the reaction? [rsa-11]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). In what form would you add the marble to slow down the reaction? [rsa-12]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). What could you reduce for the acid to slow the reaction down at the same temperature? [rsa-13]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). What could you increase for the acid to speed up the reaction at the same temperature? [rsa-14]
Calcium carbonate (limestone) were dissolved in hydrochloric acid under five different experimental conditions.
The carbon dioxide gas formed was collected in a gas syringe and the total volume of gas was recorded for the first six minutes.
The speed or 'rate of reaction' can be expressed as the rate of formation of carbon dioxide in cm3/min.
What is the average speed of the reaction in experiment W between 1 and 2 minutes in cm3/min? [rsa-15]
Calcium carbonate (limestone) were dissolved in hydrochloric acid under five different experimental conditions.
The carbon dioxide gas formed was collected in a gas syringe and the total volume of gas was recorded for the first six minutes.
The speed or 'rate of reaction' can be expressed as the rate of formation of carbon dioxide in cm3/min.
What is the average speed of the reaction in experiment X in the first half minute in cm3/min? [rsa-16]
This means a chemical reaction is? [am-1]
reversible
exothermic
endothermic
decomposition
For a chemical reaction, the word 'reversible' means? [am-4]
heat is alternately given out and taken in as the reaction proceeds
reactants can only be converted to products
the products and reactants of a reaction are in a state of balance
products can be readily converted back to reactants
A + B C + D For the type of reaction shown above, which statement is TRUE? [am-5]
from left to right is called the forward reaction
from right to left is called the equilibrium reaction
if left to right is exothermic, from right to left is also exothermic
if left to right is endothermic, from right to left is also endothermic
A + B C + D For the type of reaction shown above, which statement is TRUE? [am-6]
from left to right is called the reversible reaction
from right to left is called the backward reaction
if left to right is exothermic, from right to left is also exothermic
if left to right is endothermic, from right to left is also endothermic
A + B C + D For the type of reaction shown above, which statement is TRUE? [am-7]
from left to right is called the reversible reaction
from right to left is called the equilibrium reaction
if left to right is exothermic, from right to left is endothermic
if left to right is endothermic, from right to left is also endothermic
A + B C + D For the type of reaction shown above, which statement is TRUE? [am-7]
from left to right is called the reversible reaction
from right to left is called the equilibrium reaction
if left to right is exothermic, from right to left is also exothermic
if left to right is endothermic, from right to left is exothermic
The equation shows the effect of heat on the salt ammonium chloride. Which statement is TRUE about this reversible reaction? [am-9]
the gases formed are colourless
the formation of the solid is endothermic
ammonium gas is formed
chloride gas is formed
The equation shows the effect of heat on the salt ammonium chloride. Which statement is TRUE about this reversible reaction? [am-10]
the gases formed are colourless and green
the formation of the solid is exothermic
ammonium gas is formed
chloride gas is formed
The equation shows the effect of heat on the salt ammonium chloride. Which statement is TRUE about this reversible reaction? [am-11]
the gases formed are colourless and green
the formation of the solid is endothermic
ammonia gas is formed
chloride gas is formed
The equation shows the effect of heat on the salt ammonium chloride. Which statement is TRUE about this reversible reaction? [am-12]
the gases formed are colourless and green
the formation of the solid is endothermic
ammonium gas is formed
hydrogen chloride gas is formed
The equation shows the effect of heat on the salt ammonium chloride. Which statement is TRUE about this reversible reaction? [am-13]
the gases are formed by an endothermic reaction
the formation of the solid is a decomposition reaction
ammonium gas is formed
chloride gas is formed
The equation shows the effect of heat on the salt hydrated copper(II)
sulfate. Which statement is TRUE about this reversible reaction? [am-14]
the forward reaction (L to R) is exothermic
on heating, the hydrated solid changes colour from blue to white
the heating effect can be used as a test for water
the reaction is not reversible
The equation shows the effect of heat on the salt hydrated copper(II)
sulfate. Which statement is TRUE about this reversible reaction? [am-15]
the forward reaction (L to R) is exothermic
on heating, the hydrated solid changes colour from white to blue
the reverse reaction can be used as a test for water
the reaction is not reversible
The equation shows the effect of heat on the salt hydrated copper(II)
sulfate. Which statement is TRUE about this reversible reaction? [am-16]
the forward reaction (L to R) is exothermic
on heating, the hydrated solid changes colour from white to blue
the heating effect can be used as a test for water
the reaction is reversible
The equation shows the effect of heat on the salt hydrated copper(II)
sulfate. Which statement is TRUE about this reversible reaction? [am-17]
the forward reaction (L to R) is endothermic
on cooling the heated solid and adding water, it changes colour from blue to white
the heating effect can be used as a test for water
the reaction is not reversible
The equation shows the effect of heat on the salt hydrated copper(II)
sulfate. Which statement is TRUE about this reversible reaction? [am-18]
the reverse reaction (R to L) is endothermic
on cooling the heated solid and adding water, it changes colour from white to blue
the heating effect can be used as a test for water
the reaction is not reversible
The equation shows the effect of heat on the salt hydrated copper(II)
sulfate. Which statement is TRUE about this reversible reaction? [am-19]
the forward reaction (L to R) is exothermic
on cooling the heated solid and adding water, it changes colour from blue to white
the reverse reaction (R to L) is exothermic
the heating effect can be used as a test for water
The equation shows the effect of heat on the salt hydrated copper(II)
sulfate. Which statement is TRUE about this reversible reaction? [am-20]
the forward reaction (L to R) is exothermic
on cooling the heated solid and adding water, it changes colour from blue to white
the reverse reaction (R to L) is endothermic
the heating effect can be used to make anhydrous copper(II)
sulfate
The in the equation means the reaction is? [am-57]
reversible
decomposable
combustible
unpredictable
Which is TRUE about reversible reactions that have formed a chemical equilibrium? [am-93]
reactants are always changing into products
rate of forward reaction (L to R) is greater than the rate of the backward reaction (R to L)
the concentrations of reactants and products are constantly changing
using a catalyst increases the final amount of product formed
Which is TRUE about reversible reactions that have formed a chemical equilibrium? [am-94]
products stop changing into reactants
rate of forward reaction (L to R) is equal to the rate of the backward reaction (R to L)
the concentrations of reactants and products are constantly changing
using a catalyst increases the final amount of product formed
Which is TRUE about reversible reactions that have formed a chemical equilibrium? [am-95]
products stop changing into reactants
rate of forward reaction (L to R) is greater than the rate of the backward reaction (R to L)
the concentrations of reactants and products remain the same
using a catalyst increases the final amount of product formed
Which is TRUE about reversible reactions that have formed a chemical equilibrium? [am-96]
products stop changing into reactants
rate of forward reaction (L to R) is greater than the rate of the backward reaction (R to L)
the concentrations of reactants and products are constantly changing
using a catalyst does not increase the final amount of product formed
What is a typical pressure range in the operating conditions for the manufacture of ammonia by the Haber process? [am102]
200 to 400 atm.
1 to 10 atm.
50 to 100 atm.
600-800 atm.
What is a typical temperature range in the operating conditions for the manufacture of ammonia by the Haber process? [am103]
25 to 100oC
300 to 450oC
100 to 200oC
500 to 800oC
Which metal is used in making catalysts for the Haber synthesis of ammonia? [am104]
copper
sodium
iron
gold
Given the following symbol equation: 2Mg + O2 ==> 2MgO Calculate how many g of magnesium oxide is formed by burning 24g of magnesium in air. (Relative atomic masses, Ar: Mg = 24 and O = 16) [com-1]
40
16
20
80
Given the following symbol equation: 2Mg + O2 ==> 2MgO Calculate how many tonne of magnesium is needed to make 80 tonne of magnesium oxide. (Relative atomic masses, Ar: Mg = 24 and O = 16) [com-2]
96
48
24
16
Given the following symbol equation: CaCO3(s) ==> CaO(s) + CO2(g) Calculate how many kg of calcium carbonate is needed to make 56 kg of calcium oxide. (Relative atomic masses, Ar: Ca = 40, C = 12 and O = 16) [com-3]
50
44
100
40
Given the following symbol equation: CaCO3(s) ==> CaO(s) + CO2(g) Calculate how many g of carbon dioxide is formed if 25g of calcium carbonate is decomposed on heating to form 14g of calcium oxide. (Relative atomic masses, Ar: Ca = 40, C = 12 and O = 16) [com-4]
22
44
10
11
Given the symbol equation to show the formation of iron
sulfide: Fe + S ==> FeS Calculate the mass in g of iron sulfide formed when 5.6g of iron combines with 3.2g of
sulfur. (Relative atomic masses, Ar: Fe = 56 and S = 32) [com-5]
8.8
2.4
5.6
3.2
Given the symbol equation to show the formation of iron
sulfide: Fe + S ==> FeS Calculate the mass in g of iron sulfide formed when 28g of iron combines with 16g of
sulfur. (Relative atomic masses, Ar: Fe = 56 and S = 32) [com-6]
12
44
28
16
Given the symbol equation to show the formation of calcium chloride by burning calcium in chlorine: Ca(s) + Cl2(g) ==> CaCl2(s) Calculate the mass in g of calcium chloride formed when 20g of calcium combines with 35.5g of chlorine. (Relative atomic masses, Ar: Ca = 40 and Cl = 35.5) [com-7]
15.5
70.0
55.5
17.5
Given the symbol equation to show the formation of calcium chloride by burning calcium in chlorine: Ca(s) + Cl2(g) ==> CaCl2(s) Calculate the mass in g of chlorine needed when 40g of calcium forms 111g of calcium chloride. (Relative atomic masses, Ar: Ca = 40 and Cl = 35.5) [com-8]
80
100
151
71
Given the symbol equation to show the formation of aluminium
sulfide by heating a mixture of aluminium and sulfur: 2Al + 3S ==> Al2S3 How many g of
sulfur is needed if 54g of aluminium is reacted to form 150g of aluminium
sulfide? (Relative atomic masses, Ar: Al = 27 and S = 32) [com-9]
96
204
64
27
Given the symbol equation to show the formation of aluminium
sulfide by heating a mixture of aluminium and sulfur: 2Al + 3S ==> Al2S3 How many kg of
sulfur is needed if 108kg of aluminium is reacted to form 300kg of aluminium
sulfide? (Relative atomic masses, Ar: Al = 27 and S = 32) [com-10]
408
192
96
32
Given the symbol equation to show the formation of iron
sulfide by heating a mixture of iron and sulfur: Fe + S ==> FeS Calculate the mass in g of iron unreacted when 60g of iron reacts with 32g of
sulfur to form 88g of iron sulfide. (Relative atomic masses, Ar: Fe = 56 and S = 32) [com-11]
8
32
4
56
Given the symbol equation to show the formation of iron
sulfide by heating a mixture of iron and sulfur: Fe + S ==> FeS Calculate the mass in g of
sulfur unreacted when 28g of iron reacts with 22g of sulfur to form 44g of iron
sulfide. (Relative atomic masses, Ar: Fe = 56 and S = 32) [com-12]
22
16
12
6
Given the symbol equation to show the formation of calcium chloride by burning calcium in chlorine: Ca(s) + Cl2(g) ==> CaCl2(s) Calculate the mass in g of calcium left unreacted when 25g of calcium reacts with 35.5g of chlorine. (Relative atomic masses, Ar: Ca = 40 and Cl = 35.5) [com-13]
10.5
5.0
7.1
12.5
Given the symbol equation to show the formation of calcium chloride by burning calcium in chlorine: Ca(s) + Cl2(g) ==> CaCl2(s) Calculate the mass in g of chlorine left unreacted when 80g of calcium reacts with 150g of chlorine to form 222g of calcium chloride. (Relative atomic masses, Ar: Ca = 40 and Cl = 35.5) [com-14]
70
8
16
72
Given the equation: 2Mg(s) + O2(g) ==> 2MgO(s) and the atomic masses: Mg = 24, O = 16, how many g of magnesium is needed to make 10g of magnesium oxide? [rmc-1]
6.0
3.0
1.2
2.4
Given the equation: 2Mg(s) + O2(g) ==> 2MgO(s) and the atomic masses: Mg = 24, O = 16, how many tonne of magnesium oxide can be made from 3 tonne of magnesium? [rmc-2]
2.4
5.0
8.0
4.8
Given the equation: 2Mg(s) + O2(g) ==> 2MgO(s) and the atomic masses: Mg = 24, O = 16, what mass of oxygen in g, combines with 240g of magnesium? [rmc-3]
64
80
160
32
Iron
sulfide can be made by heating an iron and sulfur mixture. Fe(s) + S(s) ==> FeS(s) Given the atomic masses: Fe = 56, S = 32, how many g of iron
sulfide can be made from 14g of iron? [rmc-4]
44
28
16
22
Iron
sulfide can be made by heating an iron and sulfur mixture. Fe(s) + S(s) ==> FeS(s) Given the atomic masses: Fe = 56, S = 32, how many g of
sulfur reacts with 224g of iron? [rmc-5]
128
32
64
112
Iron
sulfide can be made by heating an iron and sulfur mixture. Fe(s) + S(s) ==> FeS(s) Given the atomic masses: Fe = 56, S = 32, how many g of iron is needed to make 440g of iron
sulfide? [rmc-6]
56
280
220
168
The iron ore Haematite consists mainly of iron(III) oxide. In a blast furnace it is reduced to iron with carbon monoxide ... Fe2O3(s) + 3CO(g) ==> 2Fe(l) + 3CO2(g) Given the atomic masses: Fe = 56, O =16, C=12, how many tonne of iron can be made from 40 tonnes of haematite ore? [rmc-7]
56
14
28
7
The iron ore Haematite consists mainly of iron(III) oxide. In a blast furnace it is reduced to iron with carbon monoxide ... Fe2O3(s) + 3CO(g) ==> 2Fe(l) + 3CO2(g) Given the atomic masses: Fe = 56, O =16, C=12, how many tonne of haematite ore are needed to make 224 tonne of iron? [rmc-8]
160
480
640
320
The iron ore Haematite consists mainly of iron(III) oxide. In a blast furnace it is reduced to iron with carbon monoxide ... Fe2O3(s) + 3CO(g) ==> 2Fe(l) + 3CO2(g) Given the atomic masses: Fe = 56, O =16, C=12, how g of carbon monoxide are needed to reduce 32g of iron oxide to iron? [rmc-9]
16.8
33.6
8.4
28.0
The iron ore Haematite consists mainly of iron(III)
oxide. In a blast furnace it is reduced to iron with carbon monoxide ... Fe2O3(s) + 3CO(g) ==> 2Fe(l) + 3CO2(g) Given the atomic masses: Fe = 56, O =16, C=12, how many g of carbon dioxide are formed when 80 g of haematite is reduced to iron? [rmc-10]
44
66
33
40
Lime (calcium oxide) is made by heating limestone (calcium carbonate). CaCO3(s) ==> CaO(s) + CO2(g) Given the atomic masses: Ca = 40, C = 12, O = 16, how many tonne of limestone is needed to make 112 tonne of lime? [rmc-11]
224
400
200
300
Lime (calcium oxide) is made by heating limestone (calcium carbonate). CaCO3(s) ==> CaO(s) + CO2(g) Given the atomic masses: Ca = 40, C = 12, O = 16, what mass in g of lime is made from 20g of limestone? [rmc-12]
8.8
5.6
4.4
11.2
Lime (calcium oxide) is made by heating limestone (calcium carbonate). CaCO3(s) ==> CaO(s) + CO2(g) Given the atomic masses: Ca = 40, C = 12, O = 16, how many tonne of carbon dioxide is formed by decomposing 400 tonne of calcium carbonate? [rmc-13]
176
44
88
132
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid. ZnCO3(s) + 2HCl(aq) ==> ZnCl2(aq) + H2O(l) + CO2(g) Given the atomic masses: Zn = 65, C = 12, O =16, H = 1, Cl =35.5, how many g of zinc carbonate are needed to make 68g of zinc chloride?? [rmc-14]
125.0
62.5
68.0
136.0
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid. ZnCO3(s) + 2HCl(aq) ==> ZnCl2(aq) + H2O(l) + CO2(g) Given the atomic masses: Zn = 65, C = 12, O =16, H = 1, Cl =35.5, how many g of HCl are needed to make 408g of zinc chloride? [rmc-15]
109.5
36.5
219.0
71.0
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid. ZnCO3(s) + 2HCl(aq) ==> ZnCl2(aq) + H2O(l) + CO2(g) Given the atomic masses: Zn = 65, C = 12, O =16, H = 1, Cl =35.5, what mass of zinc chloride in g can be made from 25g of zinc carbonate? [rmc-16]
54.4
12.5
13.6
27.2
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid. ZnCO3(s) + 2HCl(aq) ==> ZnCl2(aq) + H2O(l) + CO2(g) Given the atomic masses: Zn = 65, C = 12, O =16, H = 1, Cl =35.5, how many g of water are formed when 250g of zinc carbonate reacts? [rmc-17]
36
18
9
27
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid. ZnCO3(s) + 2HCl(aq) ==> ZnCl2(aq) + H2O(l) + CO2(g) Given the atomic masses: Zn = 65, C = 12, O =16, H = 1, Cl =35.5, how many g of carbon dioxide are formed when 3.65g of hydrochloric acid reacts? [rmc-18]
4.4
2.2
1.1
8.8
The salt sodium
sulfate, Na2SO4, can be made by neutralising sodium hydroxide with
sulfuric acid. 2NaOH(aq) + H2SO4(aq) ==> Na2SO4(aq) + 2H2O(l) Given the atomic masses: Na = 23, O = 16, H = 1, S = 32, how many g of sodium hydroxide is needed to make 213g of sodium
sulfate? [rmc-19]
40
80
120
160
The salt sodium
sulfate, Na2SO4, can be made by neutralising sodium hydroxide with
sulfuric acid. 2NaOH(aq) + H2SO4(aq) ==> Na2SO4(aq) + 2H2O(l) Given the atomic masses: Na = 23, O = 16, H = 1, S = 32, what mass in g of
sulfuric acid is needed to make 7.1g of sodium sulfate? [rmc-20]
9.8
14.7
19.6
4.9
The salt sodium
sulfate, Na2SO4, can be made by neutralising sodium hydroxide with
sulfuric acid. 2NaOH(aq) + H2SO4(aq) ==> Na2SO4(aq) + 2H2O(l) Given the atomic masses: Na = 23, O = 16, H = 1, S = 32, how many g of sodium
sulfate is formed when 8g of sodium hydroxide reacts? [rmc-21]
14.2
28.4
7.1
21.3
The salt sodium
sulfate, Na2SO4, can be made by neutralising sodium hydroxide with
sulfuric acid. 2NaOH(aq) + H2SO4(aq) ==> Na2SO4(aq) + 2H2O(l) Given the atomic masses: Na = 23, O = 16, H = 1, S = 32, how many g of water are formed when 49g of
sulfuric acid reacts? [rmc-22]
9
18
36
23
Copper(I)
sulfide ore can be converted to copper by roasting in air: Cu2S(s) + O2(g) ==> 2Cu(s) + SO2(g) How many g of copper can be made from 320g of the copper ore? (Relative atomic masses: Cu = 64, S = 32, O = 16) [rmc-23]
128
64
256
192
Copper(I)
sulfide ore can be converted to copper by roasting in air: Cu2S(s) + O2(g) ==> 2Cu(s) + SO2(g) How many tonnes of oxygen are needed to convert 40 tonnes of ore to copper? (Relative atomic masses: Cu = 64, S = 32, O = 16) [rmc-24]
16
32
12
8
Copper(I)
sulfide ore can be converted to copper by roasting in air: Cu2S(s) + O2(g) ==> 2Cu(s) + SO2(g) How many tonnes of
sulfur dioxide are produced for every 1280 tonnes of ore processed? (Relative atomic masses: Cu = 64, S = 32, O = 16) [rmc-25]
512
128
256
64
Copper(I)
sulfide ore can be converted to copper by roasting in air: Cu2S(s) + O2(g) ==> 2Cu(s) + SO2(g) How many tonnes of ore are needed to make 25.6 tonnes of copper? (Relative atomic masses: Cu = 64, S = 32, O = 16) [rmc-26]
64
32
48
56
Aluminium chloride can be prepared by passing dry chlorine or hydrogen chloride gas over heated aluminium metal. The equation for the hydrogen chloride reaction is: 2Al(s) + 6HCl(g) ==> 2AlCl3(s) + 3H2(g) How many kg of aluminium chloride can be made from 27 kg of aluminium? (Relative atomic masses: Al = 27.0, Cl = 35.5, H = 1.0) [rmc-27]
267.0
400.5
133.5
66.75
Aluminium chloride can be prepared by passing dry chlorine or hydrogen chloride gas over heated aluminium metal. The equation for the hydrogen chloride reaction is: 2Al(s) + 6HCl(g) ==> 2AlCl3(s) + 3H2(g) How many tonnes of hydrogen would be produced by reacting 108 tonnes of aluminium? (Relative atomic masses: Al = 27.0, Cl = 35.5, H = 1.0) [rmc-28]
2
3
6
12
Aluminium chloride can be prepared by passing dry chlorine or hydrogen chloride gas over heated aluminium metal. The equation for the chlorine reaction is: 2Al(s) + 3Cl2(g) ==> 2AlCl3(s) How much aluminium is needed to make 89 g of aluminium chloride? (Relative atomic masses: Al = 27.0, Cl = 35.5, H =1) [rmc-29]
18
27
54
9
Aluminium chloride can be prepared by passing dry chlorine or hydrogen chloride gas over heated aluminium metal. The equation for the chlorine reaction is: 2Al(s) + 3Cl2(g) ==> 2AlCl3(s) How many tonne of chlorine is needed to make 1068 tonne of aluminium chloride? (Relative atomic masses: Al = 27.0, Cl = 35.5, H = 1) [rmc-30]
71
852
426
213
Yellow lead(II) oxide ore can be reduced by heating with charcoal (carbon) in a furnace to give silvery liquid lead metal: lead(II) oxide + carbon ==> lead + carbon dioxide 2PbO(s) + C(s) ==> 2Pb(l) + CO2(g) How many tonne of lead can be made from 223 tonne of ore? (Relative atomic masses: Pb = 207, O = 16, C = 12) [rmc-31]
414.0
103.5
207.0
310.5
Yellow lead(II) oxide ore can be reduced by heating with charcoal (carbon) in a furnace to give silvery liquid lead metal: lead(II) oxide + carbon ==> lead + carbon dioxide 2PbO(s) + C(s) ==> 2Pb(l) + CO2(g) How many tonne of ore is needed to make 828 tonne of lead? (Relative atomic masses: Pb = 207, O = 16, C = 12) [rmc-32]
223
446
1784
892
Yellow lead(II) oxide ore can be reduced by heating with charcoal (carbon) in a furnace to give silvery liquid lead metal: lead(II) oxide + carbon ==> lead + carbon dioxide 2PbO(s) + C(s) ==> 2Pb(l) + CO2(g) How many kg of carbon is needed to make 828 kg of lead? (Relative atomic masses: Pb = 207, O = 16, C = 12) [rmc-33]
24
12
6
48
Yellow lead(II) oxide ore can be reduced by heating with charcoal (carbon) in a furnace to give silvery liquid lead metal: lead(II) oxide + carbon ==> lead + carbon dioxide 2PbO(s) + C(s) ==> 2Pb(l) + CO2(g) How many g of carbon dioxide are formed when 207 g of lead are produced? (Relative atomic masses: Pb = 207, O = 16, C = 12) [rmc-34]
44
22
11
33
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For reactions to occur, the particles of the reactants must collide. The fewer the collisions that take place, the slower the rate of a reaction. Which DECREASES the frequency of collision between reactant particles? [rr-1]
Calcium carbonate in the form of limestone dissolves in hydrochloric acid and giving off carbon dioxide gas. Which conditions would produce the fastest reaction? [rr-5]
Iron reacts with hydrochloric acid to form iron(II) chloride and hydrogen gas. 2g of iron is added to 100cm3 of dilute hydrochloric acid. Which conditions produces the fastest reaction? [rr-7]
A group of students carried out an experiment in which they added manganese dioxide to rapidly decompose a solution of hydrogen peroxide. To show that the manganese dioxide was acting as a catalyst, what must they do before and after the experiment? [rr-9]
When marble chips dissolve in acid, the reaction can be speeded up by? [rr-10]
Which mixture will enable the fastest reaction to take place between solid calcium carbonate (marble chips) and dilute hydrochloric acid? [rr-13]
Platinum catalyses the reaction between
sulfur dioxide SO2 and oxygen O2 to form sulfur trioxide SO3. Which of the statements 1, 2 or 3 is/are correct? [rr-15]
Sodium thiosulfate solution reacts with hydrochloric acid to form sodium chloride,
sulfur dioxide, sulfur and water. The reaction can be followed by measuring the time it takes for enough of the
sulfur precipitate to form to obscure a black cross marked on white paper. Which will decrease the time it takes for the black cross to disappear? [rr-22] 
An experiment was carried out at a temperature of 25oC by dissolving 0.2g of small limestone granules into 30cm3 of hydrochloric acid. The acid concentration was 1.0 mol/dm3 and in excess so all the limestone dissolved. The reaction was followed by measuring the volume of carbon dioxide given off over a period of 6 minutes. A 2nd experiment was done in an identical manner but using 0.2g of limestone lumps. Which of the graphs W, X, Y or Z might you expect for the results? [rr-25]
In a rates experiment the following carbon dioxide gas volumes were recorded by a student resulting from an acid-limestone reaction. The gas volume of CO2 formed at 1.5 min was omitted by accident.
Which is a chemical test for the gas hydrogen? [rr-44]
What would you increase, to increase the kinetic energy of particles involved in a chemical reaction? [rsa-1]
Limestone or marble chips are made of the chemical calcium carbonate (1). They both dissolve in hydrochloric acid (2), to produce a solution of calcium chloride (3), water (4) and carbon dioxide (5). Which of 1 to 5 is seen as the 'fizzing'? [rsa-6] 
Calcium carbonate (limestone) were dissolved in hydrochloric acid under five different experimental conditions.
This means a chemical reaction is? [am-1]
A + B 
C + D
The equation shows the effect of heat on the salt ammonium chloride. Which statement is TRUE about this reversible reaction? [am-9]
The equation shows the effect of heat on the salt hydrated copper(II)
sulfate. Which statement is TRUE about this reversible reaction? [am-14]
The 
Which is TRUE about reversible reactions that have formed a chemical equilibrium? [am-93]
Given the following symbol equation:
Given the equation: 2Mg(s) + O2(g) ==> 2MgO(s)