The mass of 1m3 of air is 1290g. Find the air mass of a room measuring 20m, 10m and 4m?

1. Let’s calculate the volume of the room by multiplying the length by the width by the height of the room:
Volume = 20 * 10 * 4 = 20 * 40 = 800 m3.
2. Multiply the weight of 1 m3 of air by 800 m3, we get the mass of air in the room:
800 * 1290 = 1032000 g = 1032 kg.
Answer: the mass of air in the room is 1032 kg.