Question

what is the missing particle?

3 1 h → ? + 3 2 he

-1 0 e
0 -1 e
1 0 he

Explanation:

Step1: Balance mass number

Mass number of \(_{1}^{3}\text{H}\) is \(3\), mass number of \(_{2}^{3}\text{He}\) is \(3\). Let mass number of missing particle be \(A\). Then \(3 = A+3\), so \(A = 0\).

Step2: Balance atomic number

Atomic number of \(_{1}^{3}\text{H}\) is \(1\), atomic number of \(_{2}^{3}\text{He}\) is \(2\). Let atomic number of missing particle be \(Z\). Then \(1=Z + 2\), so \(Z=-1\).

Answer:

\(_{-1}^{0}\text{e}\)