one of the decay products of 238u is 226ra . a rock originally contained 238u , which has a half-life of 4.5×10^9 yr, and 226ra , which has a half-life of 1,600 yr. after 5×10^9 yr, which isotopes would you expect to be present in significant amounts in the rock?

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.

answer would be option a) they have mobile charged particles.

the enthalpy change that occurs in a system when matter is transformed by a given chemical reaction, when all reactants and products are in their standard states.