Question

11) Explain what would happen to your ratio if the following happened:

a) not all of the Ag+ ions reacted with the copper metal

b) the silver was not completely dry

c) you used a different balance for each massing

__ mol Cu(s) + ___ mol AgNO3(aq) → ___ mol Ag(s) + ___ mol Cu(NO3)2(aq)

My coefficients for this stuff was 1 2 2 1 .

Data:

0.1073 g Cu 0.3037 g of Ag

silver nitrate mass 0.5050g

for ratios i used moles

0.002815:0.001688 copper : silver

0.002815:0.002973 silver : silver nitrate

Answer 1

In the given case, Cu : AgNO₃ = 0.001688 : 0.002973, i.e. 1 : 1.76

According to the given balanced equation, for 2 equivalents of AgNO₃, 1 equivalent of Cu is required for the complete reaction.

Here, for 1.76 equivalent of AgNO₃, 0.88 equivalents of Cu is required for the complete reaction.

But here, 1 equivalent of Cu is present, i.e. in an excess amount. Hence, AgNO₃ should the limiting reagent.

a) Further, the AgNO₃ is also not reacted completely.

Hence, Cu will further remain unreacted.

b) If the silver was not completely dry, the ratio would not be affected until there is a change in the ratio Cu/AgNO₃.

c) The ratio Cu/AgNO₃.,

1. If copper is more than silver nitrate, copper will remain and AgNO₃ reacts completely, as a result, the ratio Cu/Ag increases.

2. If copper is less than silver nitrate, copper will react completely and AgNO₃ remains, as a result, the ratio Cu/Ag decreases.