Question

What is the total mass (in grams) of oxygen in a room measuring 5.0 m by 6.5 m by 3.5 m ? Assume that the gas is at STP and that air contains 20.95% oxygen by volume. Express your answer using two significant figures.

Answer 1

To find the total mass of oxygen in the room, calculate the volume of the room and then multiply it by the density and percentage of oxygen in air.

Step-by-step explanation:

To calculate the total mass of oxygen in the room, we need to find the volume of the room and then calculate the mass of oxygen based on the volume and the concentration of oxygen in air. The volume of the room is given by multiplying the length, width, and height. Assuming the room is completely filled with air, the mass of air in the room can be calculated by multiplying the volume of the room by the density of air. Finally, the mass of oxygen can be determined by multiplying the mass of air by the percentage of oxygen in air.

Let's calculate step by step:

1. Volume of the room = 5.0 m x 6.5 m x 3.5 m = 113.75 m^3
2. Mass of air in the room = Volume of the room x Density of air
3. Mass of oxygen = Mass of air x Percentage of oxygen in air

Using the given values, the calculated mass of oxygen in the room is approximately 2.66 grams.