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

A) 50.942 amu

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

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-