An atomic nucleus A is composed of 84 protons and 128 neutrons. The nucleus A emits an alpha particle and is transformed into a nucleus B.

(i) What is the composition of B?

(ii) The nucleus B emits a beta particle and is transformed into a nucleus C. What is the composition of C?

(iii) What is mass number of the nucleus A?

(iv) Does the composition of C change if it emits gamma radiations?

A piece of ice of mass 60 g is dropped into 140 g of water at 50 °C. Calculate the final temperature of water when all the ice has melted. (Assume no heat is lost to the surrounding).
Specific heat capacity of water (c) = 4.2 Jg^-1k^-1,
Specific latent heat of fusion of ice (L) = 336 Jg^-1

(i) Differentiate between nuclear fusion and nuclear fission.

(ii) State one safety precaution in the disposal of nuclear waste.

The diagram below shows the change of phases of a substance on a temperature vs time graph on heating the substance at a constant rate.

(i) Why is the slope of CD less than slope of AB?

(ii) What is the boiling and melting point of the substance?