Question

what is the missing particle?
? → 3682 kr + -10 e
3582 kr 3582 br 3682 kr

Explanation:

Step1: Calculate the mass number

In a nuclear reaction, the mass number is conserved. The mass number of \(^{82}_{36}Kr\) is \(82\) and the mass number of \(^{0}_{-1}e\) is \(0\). So the mass number of the missing particle is \(82 + 0=82\).

Step2: Calculate the atomic number

The atomic number is also conserved. The atomic number of \(^{82}_{36}Kr\) is \(36\) and the atomic number of \(^{0}_{-1}e\) is \(- 1\). Let the atomic number of the missing particle be \(Z\). Then \(Z=36+( - 1)\times(-1)=35\) (using \(Z_{reactant}=Z_{product}\), \(Z = 36+1\)).

Step3: Identify the element

The element with atomic number \(35\) is \(Br\) (bromine).

Answer:

\(^{82}_{35}Br\)