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

Which of the following is in the increasing order for penetrating power

The mass of a nucleus ${ }_Z^A X$ is less that the sum of the masses of $(A-Z)$ number of neutrons and $Z$ number of protons in the nucleus. The energy equivalent to the corresponding mass difference is known as the binding energy of the nucleus. A heavy nucleus of mass $M$ can break into two light nuclei of masses $m_1$ and $m_2$ only if $\left(m_1+m_2\right)M^{\prime}$. The masses of some neutral atoms are given in the table below:

$1.$ The correct statement is:

$(A)$ The nucleus ${ }_3^6 Li$ can emit an alpha particle

$(B)$ The nucleus ${ }_{84}^{210} P_0$ can emit a proton

$(C)$ Deuteron and alpha particle can undergo complete fusion.

$(D)$ The nuclei ${ }_{30}^{70} Zn$ and ${ }_{34}^{82} Se$ can undergo complete fusion.

$2.$ The kinetic energy (in $keV$ ) of the alpha particle, when the nucleus ${ }_{84}^{210} P _0$ at rest undergoes alpha decay, is:

$(A)$ $5319$ $(B)$ $5422$ $(C)$ $5707$ $(D)$ $5818$

Give the answer question $1$ and $2.$

Alpha particles are

For the given reaction, the particle $X$ is $_6{C^{11}}{ \to _5}{B^{11}} + {\beta ^ + } + X$

What happens to the mass number and atomic number of an element when it emits $\gamma$-radiation?