Question

Chemical Reactions of Copper Pre-lab Questions and Percent Yield is experiment in the laboratory, you should be able to answer the Before b following questions. Give an example, other than Redox reaction: Co the ones listed in this experiment, of redox and metathesis reactions. metathesis: NaCl (aq) + AgNO3(aq)-ma(s), Nakoaap ,. When will reactions proceed to completion? Define percent yield in general terms. iclI is the ratio of actua vied to the . theoretical yield. % yield'actual.ficidx Theoretical yield 4. Name six methods of separating materials 5. Give criteria in terms of temperature changes for exothermic and endothermic reactions. 6. If 3.35 g of Cu(NO3)2 are obtained from allowing 2.25 g of Cu to react with excess HNO, what is the percent yield of the reaction? 7. What two liquids are flammable in this experiment?

Answer 1

2. A reaction proceeds to all the reactants are used up and none are left after the completion when completely of the reactants sot reaction 4. jy Crystallization - i) Filtration ji) Decantation iv) sublimation u Evaporation vi Distillation 5. In an released exothermic and so reaction energy is the temperature In an endothermic is absorbed and temperature falls reaction, energy so the 6. Cu + 2HNO₃ Cu(NO3)2 + H₂... excess moles of Cu = given mass = Molar mass 63.546 moles of Cu INO3) = moles of cu (since cu is the Limiting Reagent 2.25 mol 63.546

Mass of (Theoretical Cu(NO3)2 = gield) - moles & 2.25 63.546 molar mass 187.56 X 6.641 g Actual yield = 3.35 g 7. Yield Actual yield x 100 Theoretical greld 3.35 x 100 = 50.44% 6641