How many protons (p) and neutrons (n) are in an atom of Sr?
A) 38 p, 52 n
B) 38 p, 90 n
C) 52 p, 38 n
D) 90 p, 38 n

Question

How many protons (p) and neutrons (n) are in an atom of  Sr?
A) 38 p, 52 n 
B) 38 p, 90 n 
C) 52 p, 38 n 
D) 90 p, 38 n

Quizplus · Accepted Answer

The atomic symbol for strontium (Sr) denotes that it has 38 protons. The number following the element symbol (in this case, 90) represents the atomic mass, which is the sum of protons and neutrons. Therefore, we can calculate the number of neutrons by subtracting the number of protons from the atomic mass: 90 - 38 = 52. Therefore, the correct answer is 38 p, 52 n.

How Many Protons (P) and Neutrons (N) Are in an Atom