K2s+[ag(nh3)2]cl dissociation

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.

15. what volume of cci, (d = 1.6 g/cc) contain6.02 x 1025 cci, molecules (ci = 35.5)(1) 10.5 l(2) 250 ml(3) 9.625 l(4) 1.712 lplz answer with step by step explanation

In a laboratory determination of the atomic weight of tin, a sample of tin is weighed in a crucible. nitric acid is added, and the reaction proceeds to give a hydrated tin(iv)oxide plus no2and h2o. the hydrated tin(iv)oxide is then heated strongly and reacts as follows: sno2.xh2o(s)sno2(s)+ xh2o(g)the sno2is finally cooled and weighed in the crucible. explain the effect on the calculated atomic weight of tin that would result from each of the following experimental errors: (a)considerable spattering occurs when the nitric acid is added to the tin.(b)the hydrated tin(iv)oxide is not heated sufficiently to change it completely to tin oxide.