OCR GCSE 9-1 Gateway Science Chemistry QUIZ Topic C5 "Monitoring and controlling chemical reactions " (FT)

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]
1. For reactions involving gaseous reactants, decrease the pressure of the gases
2. For reactions involving solutions, raise the concentration of the solution
3. If a solid is reacting with a liquid, break the solid into smaller pieces
4. 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]
1. For reactions involving gaseous reactants, increase the pressure of the gases
2. For reactions involving solutions, decrease the concentration of the solution
3. If a solid is reacting with a liquid, break the solid into smaller pieces
4. 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]
1. For reactions involving gaseous reactants, decrease the pressure of the gases
2. For reactions involving solutions, decrease the concentration of the solution
3. If a solid is reacting with a liquid, break the solid into smaller pieces
4. 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]
1. For reactions involving gaseous reactants, decrease the pressure of the gases
2. For reactions involving solutions, decrease the concentration of the solution
3. If a solid is reacting with a liquid, use large pieces of the solid
4. 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]
1. temperature of 40°C and 10cm³ of dilute acid
2. temperature of 20°C and 10cm³ of dilute acid
3. temperature of 40°C and 5cm³ of dilute acid and 5cm³ of water
4. 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]
1. temperature of 40°C and 10cm³ of dilute acid
2. temperature of 20°C and 10cm³ of dilute acid
3. temperature of 40°C and 5cm³ of dilute acid and 5cm³ of water
4. 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]
1. iron pieces at 25°C
2. iron pieces at 50°C
3. iron powder at 25°C
4. 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]
1. iron pieces at 25°C
2. iron pieces at 50°C
3. iron powder at 25°C
4. 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]
1. BEFORE: weigh the hydrogen peroxide solution and manganese dioxide in separate containers before mixing
  AFTER: weigh both of the containers again
2. 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
3. BEFORE: weigh the manganese dioxide and then add the hydrogen peroxide solution to the beaker
  AFTER: weigh the beaker and its contents
4. 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]
1. grinding the marble chips
2. lowering the temperature
3. using a larger flask
4. using more dilute acid
When marble chips dissolve in acid, the reaction can be slowed down by? [rr-11]
1. grinding the marble chips
2. lowering the temperature
3. using a larger flask
4. 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]
1. causes the decomposition to begin
2. increases the total amount of oxygen formed
3. increases the rate at which oxygen is formed
4. 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]
1. large chips, concentrated acid, low temperature
2. low temperature, small chips, dilute acid
3. concentrated acid, high temperature, small chips
4. 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]
1. large chips, concentrated acid, low temperature
2. low temperature, large chips, dilute acid
3. concentrated acid, high temperature, small chips
4. 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. 1 and 2
2. 1 and 3
3. 2 and 3
4. 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
1. only 1
2. only 1 and 3
3. only 2 and 3
4. 1, 2 and 3
The rate of reaction between acid and marble chips can be decreased by? [rr-17]
1. warming
2. stirring
3. using larger chips
4. 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]
1. mass of acid
2. mass of marble chips
3. mass of water
4. 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]
1. limestone powder, dilute acid at 20°C
2. limestone lumps, dilute acid at 40°C
3. limestone lumps, concentrated acid at 20°C
4. 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]
1. limestone powder, dilute acid at 20°C
2. limestone lumps, dilute acid at 20°C
3. limestone lumps, concentrated acid at 40°C
4. 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]
1. doubling the temperature of the acid
2. doubling the volume of acid
3. halving the mass of the acid
4. 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]
1. increase the concentration of the hydrochloric acid
2. decrease the concentration of the sodium thiosulfate
3. cool the mixture
4. 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]
1. decrease the concentration of the hydrochloric acid
2. increase the concentration of the sodium thiosulfate
3. cool the mixture
4. 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]
1. decrease the concentration of the hydrochloric acid
2. decrease the concentration of the sodium thiosulfate
3. heat the mixture
4. add more water to the mixture
An experiment was carried out at a temperature of 25^oC 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]
1. graph line W
2. graph line X
3. graph line Y
4. graph line Z
An experiment was carried out at a temperature of 25^oC 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]
1. graph line W
2. graph line X
3. graph line Y
4. graph line Z
An experiment was carried out at a temperature of 25^oC 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]
1. graph line W
2. graph line X
3. graph line Y
4. graph line Z
An experiment was carried out at a temperature of 25^oC 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]
1. graph line W
2. graph line X
3. graph line Y
4. graph line Z
An experiment was carried out at a temperature of 25^oC 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 50^oC. Which of the graphs W, X, Y or Z might you expect for the results? [rr-29]
1. graph line W
2. graph line X
3. graph line Y
4. graph line Z
An experiment was carried out at a temperature of 25^oC 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]
1. graph line W
2. graph line X
3. graph line Y
4. graph line Z
Which will react the fastest with hydrochloric acid? [rr-31]
1. marble chips at 40^oC
2. marble chips at 25^oC
3. powdered marble at 40^oC
4. powdered marble at 25^oC
Which will react the slowest with hydrochloric acid? [rr-32]
1. marble chips at 40^oC
2. marble chips at 25^oC
3. powdered marble at 40^oC
4. powdered marble at 25^oC
An acid reacts with some tablets. The rate of reaction is decreased by? [rr-33]
1. cooling the tablets and the acid
2. crushing the tablets before adding the acid
3. stirring the tablets in the acid
4. 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]
1. their appearance is unchanged at the end of the reaction
2. they have to be a metal
3. they have to be a solid
4. 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]
1. doubling the mass of calcium carbonate
2. doubling the volume of the hydrochloric acid
3. halving the mass of the hydrochloric acid
4. 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]
1. doubling the mass of calcium carbonate
2. halving the volume of the hydrochloric acid
3. doubling the temperature
4. 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]
1. halving the mass of calcium carbonate
2. halving the volume of the hydrochloric acid
3. halving the temperature
4. 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]
1. doubling the mass of calcium carbonate
2. doubling the volume of the hydrochloric acid
3. halving the temperature
4. halving the concentration of the acid
Potatoes cook more quickly in boiling vegetable oil than in boiling water. This is because oil? [rr-39]
1. boils at a higher temperature than water
2. catalyses the cooking process
3. contains water
4. 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]
1. 18
2. 21
3. 23
4. 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]
1. 4.5 min
2. 6.0 min
3. 5.0 min
4. 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]
1. 2.0 to 2.5 min
2. 0.0 t0 0.5 min
3. 1.0 to 1.5 min
4. 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]
1. graph Q
2. graph W
3. graph Y
4. graph Z
Which is a chemical test for the gas hydrogen? [rr-44]
1. pops with lit splint
2. turns limewater cloudy
3. relights a glowing splint
4. bleaches damp litmus paper
Which is a chemical test for the gas carbon dioxide? [rr-45]
1. pops with a lit splint
2. turns limewater cloudy
3. relights a glowing splint
4. bleaches damp litmus paper
Which is a chemical test for the gas oxygen? [rr-46]
1. pops with a lit splint
2. turns limewater cloudy
3. relights a glowing splint
4. bleaches damp litmus paper
Which is a chemical test for the gas chlorine? [rr-47]
1. pops with a lit splint
2. turns limewater cloudy
3. relights a glowing splint
4. bleaches damp litmus paper
Which of the following gases is formed when a metal reacts with an acid? [rr-48]
1. hydrogen
2. carbon dioxide
3. oxygen
4. chlorine
Which of the following gases is formed when an acid reacts with a carbonate? [rr-49]
1. hydrogen
2. carbon dioxide
3. oxygen
4. chlorine
Which of the following is formed when a metal reacts with an acid? [rr-50]
1. O₂
2. Cl₂
3. H₂
4. CO₂
Which of the following is formed when a carbonate reacts with an acid? [rr-51]
1. O₂
2. Cl₂
3. H₂
4. 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]
1. graph Y
2. graph W
3. graph Q
4. 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]
1. graph W
2. graph Q
3. graph Y
4. 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]
1. graph W
2. graph Q
3. graph Y
4. 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]
1. graph W
2. graph Q
3. graph Y
4. 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]
1. graph W
2. graph Q
3. graph Y
4. 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]
1. graph line for experiment W
2. graph line for experiment X
3. graph line for experiment Y
4. 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]
1. graph line for experiment W
2. graph line for experiment X
3. graph line for experiment Y
4. 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]
1. graph line for experiment W
2. graph line for experiment X
3. graph line for experiment Y
4. 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]
1. graph line for experiment W
2. graph line for experiment X
3. graph line for experiment Y
4. 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]
1. reversible
2. exothermic
3. endothermic
4. decomposition
For a chemical reaction, the word 'reversible' means? [am-4]
1. heat is alternately given out and taken in as the reaction proceeds
2. reactants can only be converted to products
3. the products and reactants of a reaction are in a state of balance
4. 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]
1. from left to right is called the forward reaction
2. from right to left is called the equilibrium reaction
3. if left to right is exothermic, from right to left is also exothermic
4. 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]
1. from left to right is called the reversible reaction
2. from right to left is called the backward reaction
3. if left to right is exothermic, from right to left is also exothermic
4. 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]
1. from left to right is called the reversible reaction
2. from right to left is called the equilibrium reaction
3. if left to right is exothermic, from right to left is endothermic
4. 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]
1. from left to right is called the reversible reaction
2. from right to left is called the equilibrium reaction
3. if left to right is exothermic, from right to left is also exothermic
4. 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]
1. the gases formed are colourless
2. the formation of the solid is endothermic
3. ammonium gas is formed
4. 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]
1. the gases formed are colourless and green
2. the formation of the solid is exothermic
3. ammonium gas is formed
4. 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]
1. the gases formed are colourless and green
2. the formation of the solid is endothermic
3. ammonia gas is formed
4. 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]
1. the gases formed are colourless and green
2. the formation of the solid is endothermic
3. ammonium gas is formed
4. 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]
1. the gases are formed by an endothermic reaction
2. the formation of the solid is a decomposition reaction
3. ammonium gas is formed
4. 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]
1. the forward reaction (L to R) is exothermic
2. on heating, the hydrated solid changes colour from blue to white
3. the heating effect can be used as a test for water
4. 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]
1. the forward reaction (L to R) is exothermic
2. on heating, the hydrated solid changes colour from white to blue
3. the reverse reaction can be used as a test for water
4. 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]
1. the forward reaction (L to R) is exothermic
2. on heating, the hydrated solid changes colour from white to blue
3. the heating effect can be used as a test for water
4. 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]
1. the forward reaction (L to R) is endothermic
2. on cooling the heated solid and adding water, it changes colour from blue to white
3. the heating effect can be used as a test for water
4. 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]
1. the reverse reaction (R to L) is endothermic
2. on cooling the heated solid and adding water, it changes colour from white to blue
3. the heating effect can be used as a test for water
4. 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]
1. the forward reaction (L to R) is exothermic
2. on cooling the heated solid and adding water, it changes colour from blue to white
3. the reverse reaction (R to L) is exothermic
4. 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]
1. the forward reaction (L to R) is exothermic
2. on cooling the heated solid and adding water, it changes colour from blue to white
3. the reverse reaction (R to L) is endothermic
4. the heating effect can be used to make anhydrous copper(II) sulfate
The in the equation means the reaction is? [am-57]
1. reversible
2. decomposable
3. combustible
4. unpredictable
Which is TRUE about reversible reactions that have formed a chemical equilibrium? [am-93]
1. reactants are always changing into products
2. rate of forward reaction (L to R) is greater than the rate of the backward reaction (R to L)
3. the concentrations of reactants and products are constantly changing
4. using a catalyst increases the final amount of product formed
Which is TRUE about reversible reactions that have formed a chemical equilibrium? [am-94]
1. products stop changing into reactants
2. rate of forward reaction (L to R) is equal to the rate of the backward reaction (R to L)
3. the concentrations of reactants and products are constantly changing
4. using a catalyst increases the final amount of product formed
Which is TRUE about reversible reactions that have formed a chemical equilibrium? [am-95]
1. products stop changing into reactants
2. rate of forward reaction (L to R) is greater than the rate of the backward reaction (R to L)
3. the concentrations of reactants and products remain the same
4. using a catalyst increases the final amount of product formed
Which is TRUE about reversible reactions that have formed a chemical equilibrium? [am-96]
1. products stop changing into reactants
2. rate of forward reaction (L to R) is greater than the rate of the backward reaction (R to L)
3. the concentrations of reactants and products are constantly changing
4. 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]
1. 200 to 400 atm.
2. 1 to 10 atm.
3. 50 to 100 atm.
4. 600-800 atm.
What is a typical temperature range in the operating conditions for the manufacture of ammonia by the Haber process? [am103]
1. 25 to 100^oC
2. 300 to 450^oC
3. 100 to 200^oC
4. 500 to 800^oC
Which metal is used in making catalysts for the Haber synthesis of ammonia? [am104]
1. copper
2. sodium
3. iron
4. 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, A_r: Mg = 24 and O = 16) [com-1]
1. 40
2. 16
3. 20
4. 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, A_r: Mg = 24 and O = 16) [com-2]
1. 96
2. 48
3. 24
4. 16
Given the following symbol equation:
CaCO_3(s) ==> CaO_(s) + CO_2(g)
Calculate how many kg of calcium carbonate is needed to make 56 kg of calcium oxide.
(Relative atomic masses, A_r: Ca = 40, C = 12 and O = 16) [com-3]
1. 50
2. 44
3. 100
4. 40
Given the following symbol equation:
CaCO_3(s) ==> CaO_(s) + CO_2(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, A_r: Ca = 40, C = 12 and O = 16) [com-4]
1. 22
2. 44
3. 10
4. 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, A_r: Fe = 56 and S = 32) [com-5]
1. 8.8
2. 2.4
3. 5.6
4. 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, A_r: Fe = 56 and S = 32) [com-6]
1. 12
2. 44
3. 28
4. 16
Given the symbol equation to show the formation of calcium chloride by burning calcium in chlorine:
Ca_(s) + Cl_2(g) ==> CaCl_2(s)
Calculate the mass in g of calcium chloride formed when 20g of calcium combines with 35.5g of chlorine.
(Relative atomic masses, A_r: Ca = 40 and Cl = 35.5) [com-7]
1. 15.5
2. 70.0
3. 55.5
4. 17.5
Given the symbol equation to show the formation of calcium chloride by burning calcium in chlorine:
Ca_(s) + Cl_2(g) ==> CaCl_2(s)
Calculate the mass in g of chlorine needed when 40g of calcium forms 111g of calcium chloride.
(Relative atomic masses, A_r: Ca = 40 and Cl = 35.5) [com-8]
1. 80
2. 100
3. 151
4. 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, A_r: Al = 27 and S = 32) [com-9]
1. 96
2. 204
3. 64
4. 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, A_r: Al = 27 and S = 32) [com-10]
1. 408
2. 192
3. 96
4. 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, A_r: Fe = 56 and S = 32) [com-11]
1. 8
2. 32
3. 4
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, A_r: Fe = 56 and S = 32) [com-12]
1. 22
2. 16
3. 12
4. 6
Given the symbol equation to show the formation of calcium chloride by burning calcium in chlorine:
Ca_(s) + Cl_2(g) ==> CaCl_2(s)
Calculate the mass in g of calcium left unreacted when 25g of calcium reacts with 35.5g of chlorine.
(Relative atomic masses, A_r: Ca = 40 and Cl = 35.5) [com-13]
1. 10.5
2. 5.0
3. 7.1
4. 12.5
Given the symbol equation to show the formation of calcium chloride by burning calcium in chlorine:
Ca_(s) + Cl_2(g) ==> CaCl_2(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, A_r: Ca = 40 and Cl = 35.5) [com-14]
1. 70
2. 8
3. 16
4. 72
Given the equation: 2Mg_(s) + O_2(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]
1. 6.0
2. 3.0
3. 1.2
4. 2.4
Given the equation: 2Mg_(s) + O_2(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]
1. 2.4
2. 5.0
3. 8.0
4. 4.8
Given the equation: 2Mg_(s) + O_2(g) ==> 2MgO_(s)
and the atomic masses: Mg = 24, O = 16, what mass of oxygen in g, combines with 240g of magnesium? [rmc-3]
1. 64
2. 80
3. 160
4. 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]
1. 44
2. 28
3. 16
4. 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]
1. 128
2. 32
3. 64
4. 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]
1. 56
2. 280
3. 220
4. 168
The iron ore Haematite consists mainly of iron(III) oxide. In a blast furnace it is reduced to iron with carbon monoxide ...
Fe₂O_3(s) + 3CO_(g) ==> 2Fe_(l) + 3CO_2(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]
1. 56
2. 14
3. 28
4. 7
The iron ore Haematite consists mainly of iron(III) oxide. In a blast furnace it is reduced to iron with carbon monoxide ...
Fe₂O_3(s) + 3CO_(g) ==> 2Fe_(l) + 3CO_2(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]
1. 160
2. 480
3. 640
4. 320
The iron ore Haematite consists mainly of iron(III) oxide. In a blast furnace it is reduced to iron with carbon monoxide ...
Fe₂O_3(s) + 3CO_(g) ==> 2Fe_(l) + 3CO_2(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]
1. 16.8
2. 33.6
3. 8.4
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 ...
Fe₂O_3(s) + 3CO_(g) ==> 2Fe_(l) + 3CO_2(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]
1. 44
2. 66
3. 33
4. 40
Lime (calcium oxide) is made by heating limestone (calcium carbonate).
CaCO_3(s) ==> CaO_(s) + CO_2(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]
1. 224
2. 400
3. 200
4. 300
Lime (calcium oxide) is made by heating limestone (calcium carbonate).
CaCO_3(s) ==> CaO_(s) + CO_2(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]
1. 8.8
2. 5.6
3. 4.4
4. 11.2
Lime (calcium oxide) is made by heating limestone (calcium carbonate).
CaCO_3(s) ==> CaO_(s) + CO_2(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]
1. 176
2. 44
3. 88
4. 132
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid.
ZnCO_3(s) + 2HCl_(aq) ==> ZnCl_2(aq) + H₂O_(l) + CO_2(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]
1. 125.0
2. 62.5
3. 68.0
4. 136.0
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid.
ZnCO_3(s) + 2HCl_(aq) ==> ZnCl_2(aq) + H₂O_(l) + CO_2(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]
1. 109.5
2. 36.5
3. 219.0
4. 71.0
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid.
ZnCO_3(s) + 2HCl_(aq) ==> ZnCl_2(aq) + H₂O_(l) + CO_2(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]
1. 54.4
2. 12.5
3. 13.6
4. 27.2
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid.
ZnCO_3(s) + 2HCl_(aq) ==> ZnCl_2(aq) + H₂O_(l) + CO_2(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]
1. 36
2. 18
3. 9
4. 27
The salt zinc chloride can be made by dissolving zinc carbonate in dilute hydrochloric acid.
ZnCO_3(s) + 2HCl_(aq) ==> ZnCl_2(aq) + H₂O_(l) + CO_2(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]
1. 4.4
2. 2.2
3. 1.1
4. 8.8
The salt sodium sulfate, Na₂SO₄, can be made by neutralising sodium hydroxide with sulfuric acid.
2NaOH_(aq) + H₂SO_4(aq) ==> Na₂SO_4(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]
1. 40
2. 80
3. 120
4. 160
The salt sodium sulfate, Na₂SO₄, can be made by neutralising sodium hydroxide with sulfuric acid.
2NaOH_(aq) + H₂SO_4(aq) ==> Na₂SO_4(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]
1. 9.8
2. 14.7
3. 19.6
4. 4.9
The salt sodium sulfate, Na₂SO₄, can be made by neutralising sodium hydroxide with sulfuric acid.
2NaOH_(aq) + H₂SO_4(aq) ==> Na₂SO_4(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]
1. 14.2
2. 28.4
3. 7.1
4. 21.3
The salt sodium sulfate, Na₂SO₄, can be made by neutralising sodium hydroxide with sulfuric acid.
2NaOH_(aq) + H₂SO_4(aq) ==> Na₂SO_4(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]
1. 9
2. 18
3. 36
4. 23
Copper(I) sulfide ore can be converted to copper by roasting in air:
Cu₂S_(s) + O_2(g) ==> 2Cu_(s) + SO_2(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]
1. 128
2. 64
3. 256
4. 192
Copper(I) sulfide ore can be converted to copper by roasting in air:
Cu₂S_(s) + O_2(g) ==> 2Cu_(s) + SO_2(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]
1. 16
2. 32
3. 12
4. 8
Copper(I) sulfide ore can be converted to copper by roasting in air:
Cu₂S_(s) + O_2(g) ==> 2Cu_(s) + SO_2(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]
1. 512
2. 128
3. 256
4. 64
Copper(I) sulfide ore can be converted to copper by roasting in air:
Cu₂S_(s) + O_2(g) ==> 2Cu_(s) + SO_2(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]
1. 64
2. 32
3. 48
4. 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) ==> 2AlCl_3(s) + 3H_2(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]
1. 267.0
2. 400.5
3. 133.5
4. 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) ==> 2AlCl_3(s) + 3H_2(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]
1. 2
2. 3
3. 6
4. 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) + 3Cl_2(g) ==> 2AlCl_3(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]
1. 18
2. 27
3. 54
4. 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) + 3Cl_2(g) ==> 2AlCl_3(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]
1. 71
2. 852
3. 426
4. 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) + CO_2(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]
1. 414.0
2. 103.5
3. 207.0
4. 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) + CO_2(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]
1. 223
2. 446
3. 1784
4. 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) + CO_2(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]
1. 24
2. 12
3. 6
4. 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) + CO_2(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]
1. 44
2. 22
3. 11
4. 33

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

OCR GCSE 9-1 Gateway Science Chemistry QUIZ Topic C5 "Monitoring and controlling chemical reactions " (FT)

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