The pairs are:
K, Kr - Same period
Be, Mg - Same group
Ni, Tc - Both are transition metals
B, Ge - Both are metaloids
Al, Pb - Both form inert oxides
Answer:
The Empirical Formula.
Explanation:
From the empirical formula and using the weight (in g) of a given substance, we can come up with the molecular formula which is the actual weight of a substance. Sometimes, we find that the empircal formula is the molecular formula.
Answer: E. It decreases the value of Eact.
Explanation:
Activation energy is the extra energy that must be supplied to reactants in order to cross the energy barrier and thus convert to products.
A catalyst is a substance which increases the rate of a reaction by taking the reaction through a different path which involves lower activation energy and thus more molecules can cross the energy barrier and more molecules convert to products.
The catalyst itself does not take part in the chemical reaction and is regenerated as such at the end.