(Paper) Chemistry : Part I for Class XII (General Principles and Processes of Isolation of Elements - 02)

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Chemistry : Part I for Class XII
General Principles and Processes of Isolation of Elements - 02

Instructions

1. All questions are compulsory.
2. Please give the explanation for the answer where applicable.
3. To view the answer, click on the Answer link alongside the Question.
You can view the answer when the link becomesGreen Red. on completion of allocated time.


Q.1) What is the significance of leaching in extracton of aluminium? (1 Marks) 

Q.2) Although thermodynamically feasible in practice magnesium metal is not used for the reduction of alumina . Why? (1 Marks) 

Q.3) Reduction with C for Cu2O can be done at a lower temperature than ZnO. Why? (1 Marks) 

Q.4) Give the equations involved in the concentration of bauxite ore. (2 Marks) 

Q.5) Give one reaction each for roasting and calcination. (2 Marks) 

Q.6) Why is coke preferred over CO for reducing FeO? (2 Marks) 

Q.7) Give the reactions involved in the reduction of iron oxide to give iron in a blast furnace. (3 Marks) 

Q.8) How is cast iron different from pig iron? (2 Marks) 

Q.9) How is copper extracted rom low grade ores and scraps? (3 Marks) 

Q.10) How is gold extracted from its ore? (3 Marks)