) Any gas exerts a pressure against its surroundings. For example, if you put more gas in a balloon, it exerts more pressure and expands the balloon. Describe what causes the pressure in a gas, in terms of the fact that molecules of gas are moving.

Explanation:

As we know that molecules of a gas move far away from each other because they are held by weak Vander waal forces. So, when a balloon is filled by a gas then molecules of a gas strike at its walls leading to more number of collisions.

This will also lead to more expansion of the balloon. As we know that pressure is the force exerted n per unit area of a substance or object.

Thus, more is the kinetic energy of the molecules of the gas more will be the force exerted by them. Hence, more will be the pressure exerted.  

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation:

hloride, what is the mass of calcium in

explanation: