Easy crossword puzzle 9H Using Chemistry

The smaller easier KS3 Science-Chemistry crossword on "USING CHEMISTRY"

Across:
2	If burning reactions were not of this type of reaction, fuels wouldn't be much good as an energy resource! (10)
5	This type of crop, whatever its benefits, is causing great controversy. (2)
7	A medicine which is usually a good remedy for a headache, but is proving valuable for other medical conditions including heart attack prevention. (7)
9	They may be nasty chemicals but they stop this in wood! (3)
10	A sort of desire to make the best fuel! (7)
13	Typical last part of the name of compound we extract metals from. (5)
14	A simple one of these is made by dipping connected zinc and copper strips into salt or acid solution but we are built of different type of (4)?
16	Our energy releasing process, by lots of amazing enzyme catalysed reactions. (11)
17	Cars don't run too well without it! (4)
18	Initials of a pesticide that is banned in most counries due to its buildup, and harmful effects, in food chains. (3)
19	The metal used with carbon in the original 'ever ready' battery. (4)
21	Useful chemical for washing hands! (4)
22	A crucial element in ancient and modern metal extraction. (6)
24	The result of any chemical reaction, it makes a new (7)?
27	This is released as heat or electricity when chemicals react. (6)
28	This is conserved in any chemical change. (4)
29	The chemical warfarin will kill it! (3)
30	Mixing chemicals to give an exothermic reaction can be used as a hand (6)?
31	It comes along in so many synthetic colours these days. (3)
32	An ideal fuel, no pollution, on burning just water formed! (8)

Down:
1	The law of (12)? of mass
3	Handy tool that goes with small boats, once made of wood, more likely to be plastic these days? (3)
4	A platinum and rhodium catalyst convert this gas into harmless CO₂ in car exhausts. (6,8)
6	A powder of this metal gives bright white flashes to fireworks. (9)
8	The Egyptians almost certainly did NOT make one of these by sticking connected strips of copper and zinc into a citrus fruit! (7)
11	Not very big from a single battery but can add together in series to increase it or use a more reactive metal? (7)
12	A modern material replacing many metals in various products and a common name for a polymer. (7)
15	A long molecule made into many useful products. (7)
20	Can be spontaneous but usually achieved using a match or spark! (10)
23	When the lungs ain't so good, cylinders of this save lives both in the home as well as in in hospitals. (6)
25	Coat this with the sticky product left over from distilling crude oil. (4)
26	Sythetic fibres made of plastic are much used now in this industry. (7)