Question

question 1 0.25 pts how many neutron are in an atom of calcium-40? question 2 0.25 pts how many neutron are in an atom of phosphorus-31?

Explanation:

Question 1

Step1: Recall atomic number of Ca

Calcium (Ca) has an atomic number ($Z$) of 20, meaning it has 20 protons. The mass number ($A$) of calcium - 40 is 40.

Step2: Use neutron formula

The formula to find the number of neutrons ($N$) is $N=A - Z$. Substitute $A = 40$ and $Z = 20$ into the formula: $N=40 - 20$.

Step1: Recall atomic number of P

Phosphorus (P) has an atomic number ($Z$) of 15, so it has 15 protons. The mass number ($A$) of phosphorus - 31 is 31.

Step2: Use neutron formula

Using the formula $N = A - Z$, substitute $A=31$ and $Z = 15$: $N=31 - 15$.

Answer:

20

Question 2