3. The test tube that contained the calcuim metal was probably the most difficult of the test tubes to clean. Why was aqueous HCl used to clean the tube

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.

particle   p is an electron and particle q is a neutron

the answers would be

the first one and the second one