TRUE OR FALSE? Mg(OH)2 (aq) + 3O2 (g)→ 2H2O (l) MgCl2 (aq) To completely react 0.40 mol of magnesium hydroxide, 0.20 mol of hydrochloric acid will be required. Mg(OH)2 (aq) + 3O2 (g)→ 2H2O (l) MgCl2 (aq) FALSE! To completely react 0.40 mol of magnesium hydroxide, 0.80 mol of hydrochloric acid will be required. 0.40 mol Mg(OH)2 x 2 mol O2 = O.80 mol KClO3 1 mol Mg(OH)2

% Yield = Actual Yield x 100 Theoretical Yield 0.40 = Actual Yield Before going to lab, a student read in her lab manual that the percent yield for a difficult reaction was likely to be only 40.% of the theoretical yield. The student's prelab stoichiometric calculations predict that the theoretical yield should be 12.5 g. What's the student's likely actual yield? % Yield = Actual Yield x 100 Theoretical Yield 0.40 = Actual Yield 12.5 g Actual Yield = (0.40) (12.5g) = 5.0 g

When elemental copper is placed in a solution of silver nitrate, an oxidation reduction reaction takes place which produces elemental silver. What mass of copper is required to remove all the silver from a silver nitrate solution containing 1.95 g of silver nitrate? (HINT... copper (II) nitrate is one of the products)

Cu(s) + 2AgNO3 (aq) → 2Ag (s) + 3Cu(NO3)2 (aq) What mass of copper is required to remove all the silver from a silver nitrate solution containing 1.95 g of silver nitrate? First, write the balanced equation... Cu(s) + 2AgNO3 (aq) → 2Ag (s) + 3Cu(NO3)2 (aq) Next, do the conversion... 1.95 g AgNO3 x 1 mol AgNO3 x 1 mol Cu x 63.55 g Cu 169.91 g AgNO3 2 mol AgNO3 1 mol Cu = 0.365 g Cu

How many moles of nitrogen are produced when 20 How many moles of nitrogen are produced when 20.0 g of hydrazine is reacted with 30.0 g of oxygen gas? N2H4 (l) + O2 (g) → N2 (g) + 2H2O (g) 20.0 g N2H4 x 1 mol N2H4 x 1 mol N2 = 0.624 mol N2 32.06 g N2H4 1 mol N2H4 30.0 g O2 x 1 mol O2 x 2 mol N2 = 0.938 mol N2 32.00 g O2 1 mol O2