many moles are in 3.46 x 10^22 molecules of phosphoric acid?

3.105 Nitric acid is often sold and transported as a concentrated 16 M aqueous solution. How many gallons of such a solution would be needed to contain the roughly 2.1109 pounds of HNO3 produced annually in the United States?

4.69 The pictures below show a molecular-scale view of a chemical reaction between H2 and CO to produce methanol, CH3OH. The box on the left represents the reactants at the instant of mixing, and the box on the right shows what is left once the reaction has gone to completion. Was there a limiting reactant in this reaction? If so, what was it? Write a balanced chemical equation for this reaction. As usual, your equation should use the smallest possible whole number coefficients for all substances.

3.121 If you have 21.1 g of iron(II) nitrate that is dissolved to give 1.54 L of solution, what is the molarity of the solution? What is the molarity of the nitrate ions?