Answer to Question #56493 in General Chemistry for jocelyn

Question

a)a student tested a solution with a ph meter and recorded the ph to be 7.43. calculate the [H3O+] and [OH-] for this solution

b)a 2.291g sample containing sulfate ions was treated with barium to precipitate barium sulfate (BaSO4; MW=233.4g/mol) if the collected precipitate weighed 3.0687g was the unknown sample sodium sulfate (Na2SO4; MW-142.0g/mol) or potassium sulfate (K2SO4; MW=174.2g/mol) support your answer with calculations

c)consider the balanced reaction between Cu and nitric acid shown below. If 1.55g of Cu (NO3)2 (mw=187.6g/mol) was obtained from the reaction of 0.95g of Cu(mw=63.55g/mol) excess HNO3 what is the % yield of the reaction?
Cu(s) +4HNO3(aq)-> Cu(NO3)2(aq)+2NO2(g)+2H2O(l)