Air is made up of gas particles. these particles exert pressure on every object they collide against. this pressure is known as air pressure. which of the following statements about air pressure is true?

Complete Question:

Air is made up of gas particles. These particles exert pressure on every object they collide against. This pressure is known as air pressure. Which of the following statements about air pressure is true?

A. The atmosphere's air pressure does not vary;

B. Air pressure decreases as altitude increases;

C. Air pressure increases as altitude increases;

D. Warm air tends to have a higher air pressure than cold air.

B.

Explanation:

The air pressure depends on the movement of the molecules, so as many molecules presented, as higher is the pressure. When the altitude increases, the top of the atmosphere is being closed, so there's less amount of air. It means there are fewer molecules, so the pressure will decrease.

As higher is the temperature, as more agitated are the molecules, so they are more dispersed, and the pressure is low. So, warm air intends to have a lower air pressure than cold air.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.