5291217
Description
Flashcards by Ella Maggs, updated more than 1 year ago
|
Created by Ella Maggs
over 8 years ago
|
|
| Question | Answer |
| What is the symbol equation for the Haber process? | N2 + 3H2 <--> 2NH3 |
| What is the word equation for the Haber process? | nitrogen + hydrogen <--> ammonia |
| What is ammonia used for? | It is used for fertilisers. |
| What is the optimum temperature? | 450C, which is reasonably low for a industrial process. |
| What is the optimum pressure? | 200 atmospheres/ 20 MPa, this is quite high. |
| Name two other optimum conditions. | Use a iron catalyst, and recycle the unreacted hydrogen and nitrogen. |
| Why are optimum conditions used? | They make the process as efficient as possible, this meaning nothing is wasted and the process is cheap. |
| What is percentage yield? | A 100% yield means that no product has been lost, while a 0 per cent yield means that no product has been made. So, it means the percentage of product made from the materials. |
| What does rate of reaction mean? | This is the speed of how quickly the reaction happens. |
| Why is a iron catalyst used? | It increases the rate of reaction, but not the percentage yield. |
| What does a high pressure do? | It increases the the percentage yield of ammonia. |
| A high temperature increases what? | It increases the rate of reaction. |
| A high temperature decreases what? | The percentage yield. |
| Why is the temperature 450c? | It is a compromise, the best of a "bad balance". The yield is not high, but the the rate is fairly quick. |
| Why do chemical plants not aim for the best yield? | Costs increase when the temperature and pressure increase, this making it not cost effective. They aim for the best economical yield. |
Want to create your own Flashcards for free with GoConqr? Learn more.