How many protons (p)and neutrons (n)are in an atom of ${ } _ { 38 } ^ { 90 } \mathrm { Sr }$?
A)38 p,52 n
B)38 p,90 n
C)52 p,38 n
D)90 p,38 n

Question

Quizplus · Accepted Answer

The number above the element symbol represents the mass number, which is the sum of protons and neutrons. Therefore, the number of protons is equal to the atomic number or the number of the element, which in this case is 38. Subtracting 38 from 90 gives us the number of neutrons, which is 52. Therefore, the correct answer is A, 38 p and 52 n.

How Many Protons (P)and Neutrons (N)are in an Atom Of 3890Sr{ } _ { 38 } ^ { 90 } \mathrm { Sr }3890​Sr

How Many Protons (P)and Neutrons (N)are in an Atom Of ${ } _ { 38 } ^ { 90 } \mathrm { Sr }$