A certain radioactive nucleus emits a particle that leaves it's mass number unchanged, but increases it's atomic number by one. Identify the particle and write it's symbol.

What happens to the (i) atomic number, (ii) mass number of the nucleus of an element when (a) an α particle, (b) a β particle, and (c) γ radiation, is emitted?

Complete the following sentences:

(a) The mass number and atomic number of an element are not changed when it emits ……………

(b) The atomic number of a radioactive element is not changed when it emits ……………

(c) During the emission of a beta particle, the …………… number remains same.

Complete the following nuclear changes —

(a) $_{x}^{a}\text{P} \longrightarrow Q + _{-1}^{0}\text{β}$
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(b) $_{92}^{238}\text{U} \longrightarrow \space _{90}^{234}\text{Th} + …… + \text{energy}$

(c) $_{92}^{238}\text{P} \overset{\alpha} \longrightarrow \text{Q} \overset{\beta} \longrightarrow \text{R} \overset{\beta} \longrightarrow \text{S}$

(d) {Z}^{A}\text{X} \overset{\alpha} \longrightarrow \text{X}{1} \overset{\gamma} \longrightarrow \text{X}{2} \overset{2\beta} \longrightarrow \text{X}{3}

(e) $\text{X} \overset{\beta} \longrightarrow \text{X}${1} \overset{\alpha} \longrightarrow \text{X}{2} \overset{\alpha} \longrightarrow \space {69}^{172}\text{X}{3}