The following observations were made by a student on treating four metals P, Q, R and S with the given salt solutions:

Based on the above observations:

(a) Arrange the given samples in the increasing order of reactivity

(b) Write the chemical formulae of products formed when Q reacts with CuSO₄ solution.

State the events occurring during the process of photosynthesis. Is it essential that these steps take place one after the other immediately?

● Absorption of light energy by chlorophyll.

● Conversion of light energy to chemical energy and splitting of water molecules into hydrogen and oxygen.

● Reduction of carbon dioxide to carbohydrates.

Give a test that can be used to confirm the presence of carbon in a compound. With a valency of 4, how is carbon able to attain noble gas configuration in its compounds?

OR

The number of carbon compounds is more than those formed by all other elements put together. Justify the statement by giving two reasons.

A student observes the above phenomenon in the lab as a white light passes through a prism. Among many other colours, he observed the position of the two colours Red and Violet.

What is the phenomenon called? What is the reason for the violet light to bend more than the red light?

A student has two resistors- 2 Ω and 3 Ω. She has to put one of them in place of R2 as shown in the circuit. The current that she needs in the entire circuit is exactly 9A. Show by calculation which of the two resistors she should choose