general chem
posted by rob .
Calculate the molarity of a solution made by dissolving 12.5 grams of Na2CrO4 in enough water to form exactly 550 mL of solution. (b) How many moles of KBr are present in 150 mL of a 0.275 M solution? (c) How many milliters of 6.1 M HCl solution are needed to obtain 0.100 mol of HCl?

a) molarity= moles/liters convert grams to moles, then solve.
b) same formula, solve for moles
c) sam formula, solve for volume inliters, then convert to ml. 
A .105L sample of unknown HNO3 required 46.5mL of .150M Ba(OH)2 for complete neutralization. What is concentration of HNO3