Question

All alpha particles have a charge of

• A. 0.0
• B. - 2
• C. 1
• D. 2

Answer 1

The correct option is D 2

An alpha ($\alpha$) particle is a doubly ionised helium nucleus, i.e. a helium atom whose two electrons have been removed. During the process of $\alpha$-emission, an $\alpha$-particle is emitted thereby decreasing the mass number of the parent nucleus by 4 and the atomic number by 2.
$AZX\to A-4Z-2Y+42\mathrm{He}$
So, an alpha particle $\left({\text{He}}^{2+}\right)$ has a positive electric charge of two.