Question

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

Explanation:

Step1: Recall sodium's atomic number

Sodium (Na) has an atomic number of 11. The atomic number is equal to the number of protons.

Step2: Use mass - number formula

The mass number is the sum of protons and neutrons. Let the number of neutrons be $n$, the number of protons be $p$, and the mass number be $A$. So $A=p + n$. Given $A = 22$ and $p=11$.

Step3: Solve for number of neutrons

We can rewrite the formula as $n=A - p$. Substitute $A = 22$ and $p = 11$ into the formula: $n=22-11 = 11$.

Answer:

1. Option with 11 is the correct answer among the given choices.