Question

for mg 2+ with 13 neutrons what is the mass number *
54
22
56
13
25
100
131
44
78
40
12
11
53
10

Explanation:

Step1: Identify atomic number of Mg

Magnesium (Mg) has an atomic number of 12. The atomic number is the number of protons in an atom's nucleus and remains the same even when the atom forms an ion.

Step2: Recall mass - number formula

The mass number (A) of an atom is given by the sum of the number of protons (p) and neutrons (n), i.e., $A=p + n$.

Step3: Calculate mass number

We know that the number of protons of Mg is 12 (from its atomic number) and the number of neutrons is 13. So, $A=12 + 13=25$.

Answer:

25