What gas makes up 78% of our atmosphere?
Nitrogen
When a candle burns, what happens to the oxygen?
It is burned up.
The condition of Earth’s atmosphere at a particular time and place is called….
Weather
T or F Smoke is made up of solid particles in the air.
True
What gas makes up 21% of our atmosphere?
Oxygen
The atmosphere protects us from harmful rays of the sun plus…..
meteoroids
Water vapor is a liquid and steam is a gas.
True
The more molecules in a volume of air, the greater it’s …..
Density
Plants take in carbon dioxide and give off ….
Oxygen
Air has mass because it is composed of …..
Atoms and Molecules
Density increases if we put ___ molecules in it.
More
The amount of oxygen is less at high or low altitudes?
High
What do we call an instrument used to measure air pressure?
Barometer
As air pressure decreases, what happens to the column of mercury?
It sinks
Mercury is one type of barometer. Name another type.
Aneroid
Inches of mercury is one way we express air pressure. What is another?
Millibars
What is another word for elevation?
Altitude
Air pressure is weakest.
On a mountain top