Question

The molecular mass of air, at standard pressure and temperature, is approximately 28.97 g/mol. Calculate the mass of 3.33 moles of air.
First, complete the unit conversion using dimensional analysis:

A ×
B
C
= ? g Air

A:
B:

Answer 1

A: 3.33 mol Air

B: 28.97 g Air

C: 1 mol Air

Answer 2

Answer:

               Mass = 96.47 g

Solution:

Data Given:

                  M.Mass  =  28.97 g.mol⁻¹

                  Moles  =  3.33 mol

                  Mass  =  ??

Formula Used:

                  Moles  =  Mass ÷ M.Mass

Solving for Mass,

                  Mass  =  Moles × M.Mass

Putting values,

                  Mass  =  3.33 mol × 28.97 g.mol⁻¹

                  Mass  =  96.4701 g

Rounding to four significant numbers,

                 Mass = 96.47 g