Question

what is the missing particle?

82 35 br → ? + 0 - 1 e

82 36 kr

82 35 kr

82 35 br

Explanation:

Step1: Balance the atomic number

The atomic number of \(Br\) is \(35\). For the right - hand side, let the atomic number of the missing particle be \(Z\). We know that \(35=Z+( - 1)\). Solving for \(Z\), we get \(Z = 36\).

Step2: Balance the mass number

The mass number of \(Br\) is \(82\). Let the mass number of the missing particle be \(A\). We know that \(82=A + 0\). Solving for \(A\), we get \(A = 82\).

Step3: Identify the element

The element with atomic number \(Z = 36\) is \(Kr\).

Answer:

\(\ce{^{82}_{36}Kr}\)