# In the equation: "_90^234Th -> "_91^234Pa + X, which particle is represented by X?

Feb 1, 2017

The particle is an electron =""_-1^0e

#### Explanation:

${\text{_90^234Th->}}_{91}^{234} P a + X$

We have conservation of the number of nucleons and charge number

For $X$, the number of nucleons is $= 0$ and the charge number is $= - 1$

 ""_-1^0 X

This particle is ${\beta}^{-}$ which is an electron ""_-1^0e