# Given the nuclear equation ""_1^1H + X -> _3^6Li + _2^4He, what is the particle represented by X?

Apr 8, 2018

""_4^9Be

#### Explanation:

We have the nuclear equation:

${\text{_1^1H+X->""_3^6Li+}}_{2}^{4} H e$

In a nuclear equation, the total mass and the number of protons stay the same.

There is only $1$ mass unit on the left side, but $6 + 4 = 10$ units on the left side. This tells us element $X$ has a mass of $10 - 1$ units.

Also, there is only $1$ proton on the left side, but $3 + 2 = 5$ protons on the right side. So, element $X$ must have $5 - 1 = 4$ protons.

The element with four protons on the periodic table is beryllium, and its symbol is $B e$. Thus, the complete equation for this reaction is:

${\text{_1^1H+""_4^9Be->""_3^6Li+}}_{2}^{4} H e$