What is the active site of an enzyme?

the hydrogen atoms that can form hydrogen bonds

the section of the molecule that interacts with a substrate

the carboxylic acid group at the end of the protein chain

the group of amino acids in the middle of the protein chain

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

Select all that apply. using a value of ksp = 1.8 x 10-2 for the reaction pbcl2 (s) pb+2(aq) + 2cl -(aq). the concentration of the products yield a ksp of 2.1 x 10-2:

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.