Answer:
The mass number is 267.
Explanation:
It is given that,
Number of electrons are 109
Number of neutrons are 158
Charge is +1
We need to find the mass number of the ion.
We know that,
Mass number = No. of neutrons+ No. of protons
Also, No. of protons = No. of electrons = 109
So,
Mass number = 109+158 = 267
Therefore, the mass number is 267.
