In a chemical reaction, 300 grams of reactant a are combined with 100 grams of reactant b. both a and  b react to completion. how much will the product weigh?

400 grams. Due to the law of consevation of mass. It states that mass quantitu must remain constant.

Potassium and rubidium are both larger than lithium because atomic size increases going down in a group. The reason for the effective nuclear charge trend has to do with inner electrons that shield the outer electrons from the nuclear charge.

Explanation: