Question

A element has 7 electrons and 8 neutrons the mass no of element is

Answer 1

15

Answer 2

Given:

• Number of electrons = 7
• Number of neutrons = 8

Assuming the element is a neutral atom, the number of protons is equal to the number of electrons.

Number of protons = Number of electrons = 7

The mass number (A) of an element is the sum of the number of protons (Z) and the number of neutrons (N) in the nucleus.

Mass number (A) = Number of protons + Number of neutrons

A = 7 + 8

A = 15

The mass number of the element is 15. This element is Nitrogen (N), as it has 7 protons. The specific isotope is $^{15}$N.

Solution:

Number of electrons = 7

Assuming a neutral atom, Number of protons = 7

Number of neutrons = 8

Mass number = Number of protons + Number of neutrons = 7 + 8 = 15.