Zinc metal is added to hydrochloric acid to generate hydrogen gas, which is collected over water at 20.0°C (18 torr). The total pressure is 615.6 torr. Determine the partial pressure of the hydrogen gas in this mixture.

i'm assuming that the correct answer is indeed the first one/ "a"..

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.