Question

The naturally occurring isotopes of vanadium are vanadium-50 and vanadium-51. Vanadium-50 has an abundance of 0.250%

and a mass of 49.947 amu. Vanadium-51 has an abundance of 99.750% and a mass of 50.944 amu. Calculate the average atomic
mass of vanadium
50.942 amu
62.558 amu
63.303 amu
5094151 amu

Answer 1

A) 50.942 amu

Step-by-step explanation:

Data Given:

Abundance of V-50 = 0.25 % = 0.0025

mass of V-50 = 49.947 amu

Abundance of V-51 = 99.750% = 0.9975

mass of V-51 = 50.944 amu

Average atomic mass of Vanadium = ?

Solution:

Formula used to check average atomic mass is as under

Average atomic mass = m₁A₁ + m₂A₂

Where

m₁ and m₂ = mass of isotope 1 and 2 respectively

A₁ and A₂ = abundance or fraction of isotope 1 and 2 respectively

Put values in above formula

Average atomic mass = (49.947 amu)(0.0025) + (50.944 amu)(0.9975)

Average atomic mass = 0.1248675 + 50.81664

Average atomic mass = 50.9415075 amu

So

Round to four significant figures

Average atomic mass of V = 50.942 amu

option A is correct