For metals,
as you go down a group.
for nonmetals,
as you go down a group.

Can someone me with questions 12 and 13 plz.

This drawing shows a human body system. what is the primary function of this body system?

Which statement is true about a catalyst? a: a catalyst decreases the rate of the reaction. b. a catalyst is consumed during a chemical reaction. c. a catalyst lowers the activation energy of a reaction. d. a catalyst increases the reactant concentration during a reaction.