Answer to Question #295568 in Chemistry for cols

Question

Bismuth-213 is used in radiation therapy to treat leukemia, while strontium-89 is utilized to treat bone metastasis. Write the isotopic symbols of the two atoms. How many protons and neutrons does each atom have?

Answer 1

Solution:

A = mass number

Z = atomic number (number of protons)

N = number of neutrons

A = Z + N

(1):

Bismuth-213 = ²¹³Bi

So ²¹³Bi has a mass number (A) of 213, which is the sum of the protons (Z) and neutrons (N) in the nuclei of that isotope's atoms.

The number of protons (Z) is the atomic number of bismuth (Z = 83; according to the periodic table).

So the number of neutrons is: N = A - Z = 213 - 83 = 130.

Answer (1): Bismuth-213: Z = 83; N = 130.

(2):

Strontium-89 = ⁸⁹Sr

So ⁸⁹Sr has a mass number (A) of 89, which is the sum of the protons (Z) and neutrons (N) in the nuclei of that isotope's atoms.

The number of protons (Z) is the atomic number of strontium (Z = 38; according to the periodic table).

So the number of neutrons is: N = A - Z = 89 - 38 = 51.

Answer (2): Strontium-89: Z = 38; N = 51.