When a nucleus with atomic number $Z$ and mass number $A$ undergoes a radioactive decay process :

A plot of the number of neutrons $(N)$ against the number of protons ( $P$ )of stable nuclei exhibits upward deviation from linearity for atomic number, $Z>20$. For an unstable nucleus having $N / P$ ratio less than $1$ , the possible mode($s$) of decay is(are)

($A$) $\beta^{-}$-decay ( $\beta$ emission)

($B$) orbital or $K$-electron sasture

($C$) neutron emission

($D$) $\beta^{+}$-decay (positron emission)

When a radioactive substance emits an $\alpha$- particle, its position in the periodic table is lowered by

A radioactive nucleus with $Z$ protons and $N$ neutrons emits an $\alpha - $ particle, $2\beta$- particles and $2$ gamma rays. The number of protons and neutrons in the nucleus left after the decay respectively, are

Write nuclear reaction equations for

$(i)$ $\alpha$ -decay of $^{226}_{88} Ra$

$(ii)$ $\alpha$ -decay of $_{94}^{242} Pu$

$(iii)$ $\beta$ -decay of $_{15}^{32} P$

$(iv)$ $\beta$ -decay of $^{210}_{83}Bi$

$(v)$ $\beta^{+}$ -decay of $_{6}^{11} C$

$(vi)$ $\beta^{+}$ -decay of $_{43}^{97} Tc$

$(vii)$ Electron capture of $^{120}_{54} Xe$

In the given reaction $_z{X^A}{ \to _{z + 1}}{Y^A}{ \to _{z - 1}}{K^{A - 4}}{ \to _{z - 1}}{K^{A - 4}}$ Radioactive radiations are emitted in the sequence