Question

The density of air at ordinary atmospheric pressure and 25 ℃ is 1.19 g/L. What is the mass, in kilograms, of the air in a room that measures 14.5 × 18.5 × 9.0ft?

Express your answer using two significant figures.

Answer 1

Answer – Given, density = 1.19 g/L , room measurements = 14.5 × 18.5 × 9.0ft

We know the volume = 14.5 ft × 18.5 ft × 9.0 ft

                                   = 2414.25 ft³

We need to convert the ft³ to dm³

1 ft³ = 28.32 dm³

So, 2414.25 ft³ = ?

= 68363.9 dm³

We know, 1 dm³ = 1 L

So, 68363.9 L

So, mass of air = density * volume

                         = 1.19 g/L *68363.9 L

                         = 81353.04 g

                         = 81.35 kg

So answer in two significant figure is 81 kg