Question

Determine the number of neutrons for the given isotopes. helium-3 carbon-14 nitrogen-15 strontium-90 tellurium-123

Answer 1

helium-3 has 1 neutron
carbon-14 has 8
nitrogen-15 has 8 (I think)
strontium-90 has 52
tellurium-123 has 71

Answer 2

Answer: Number of neurons in

Helium = 1

Carbon = 8

Nitrogen = 8

Strontium = 52

Tellurium = 71

Step-by-step explanation: Isotopes are the forms of same element having different mass numbers. They only differ in the number of neutrons. The number of protons remain same.
`_(Z)^(A)\textrm{X}` and
`_(Z)^(B)\textrm{X}` are the two isotopes of same element X.

Neutrons can be calculated by:

Number of neutrons = Mass Number - Number of neutrons

and Atomic Number = Number of protons

For the given elements, Mass numbers are given

Atomic Number of Helium = 2

Given mass number = 3

Number of neutrons in Helium= (3 - 2) = 1

Similarly,

Number of neutrons in Carbon = (14 - 6) = 8

Number of neutrons in Nitrogen = (15 -7) = 8

Number of neutrons in Strontium = (90 - 38) = 52

Number of neutrons in Tellurium = (123 - 52) = 71