In each fission reaction, the …………… remains conserved.

1. mass number
2. atomic number
3. mass
4. both (1) and (2)

Which of the following is used as moderator(s) in a nuclear reactor ?

1. Cadmium rods
2. Graphite
3. Heavy Water
4. Both (2) and (3)

The temperature required for the process of nuclear fusion is nearly:

1. 1000 K
2. 10⁴ K
3. 10⁵ K
4. 10⁷ K

Complete the following nuclear fission reactions:

(a) ${}_{92}^{235}\text{U}${92}^{235}\text{U} + ${0}^{1}\text{n}$ ⟶ ${}_{56}\text{Ba}${56}\text{Ba} + $^{92}\text{Kr}$ + 3 ${0}^{1}\text{n}$ + …….

(b) ${}_{92}^{235}\text{U}${92}^{235}\text{U} + ${0}^{1}\text{n}$ ⟶ $^{148}\text{La}$ + ${}_{35}^{85}\text{Br}${35}^{85}\text{Br}+ …… ${0}^{1}\text{n}$ + energy