(SK015) Naturally occurring argon consists of thre isotopes , argon-36, argon-38, argon-40 in the ratio of 4.86: 1 : 1423 i) Calculate the percentage composition of the three isotopes. ii) Calculate the relative atomic mass of argon to four significant figures.

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.