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| 2 | Process for producing ammonia from nitrogen and hydrogen | 
 
 
| 4 | A negatively charged electrode | 
 
 
| 5 | A type of rock formed by high heat and pressure | 
 
 
| 6 | The crust and top part of the mantle | 
 
 
| 7 | A positively charged electrode | 
 
 
| 8 | In the mantle causes the plates to move | 
 
 
| 10 | Used to make fertilisers | 
 
 
| 11 | The theory of Alfred Wegner | 
 
 
| 12 | A type of rock that is formed by the deposition of material | 
 
 
| 14 | Solution used to purify copper | 
 
 
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