What are Hari Singh’s reactions to the prospect of receiving an education? Do they change over time? (Hint: Compare, for example, the thought: “I knew that once I could write like an educated man there would be no limit to what I could achieve” with these later thoughts: “Whole sentences, I knew, could one day bring me more than a few hundred rupees. It was a simple matter to steal — and sometimes just as simple to be caught. But to be a really big man, a clever and respected man, was something else.”) What makes him return to Anil?

Why does the sky appear dark instead of blue to an astronaut?

Explain the following in terms of gain or loss of oxygen with two examples each. 
(a) Oxidation
(b) Reduction

Draw the structure of a neuron and explain its function.

Write the balanced chemical equations for the following reactions. 
(a) Calcium hydroxide + Carbon dioxide \(→\) Calcium carbonate + Water 
(b) Zinc + Silver nitrate \(→\) Zinc nitrate + Silver 
(c) Aluminium + Copper chloride \(→\) Aluminium chloride + Copper 
(d) Barium chloride + Potassium sulphate \(→\) Barium sulphate + Potassium chloride