An isotope of iron (Fe) has 26 protons and 32 neutrons.

Question

An isotope of iron (Fe) has 26 protons and 32 neutrons.

 

a. What is the approximate mass of this isotope?

 

b. Write the symbol for this isotope.

Answer 1

(a)

 

proton mass = 1.673 x 10^-27 kg

neutron mass = 1.675 x 10^-27 kg

 

Mass of the isotope:

 

M = [26(1.673 x 10^-27) + 32(1.675 x 10^-27)] kg = 9.710 x 10^{-26 kg}

 

(b)

 

Mass number = 26 + 32 = 58

Atomic number = 26

 

Symbol:

 

⁵⁸₂₆Fe