Limiting reagents help

Question

Solutions of sodium carbonate and silver nitrate react to form solid silver carbonate and a solution of sodium nitrate. A solution containing 7.75 g of sodium carbonate is mixed with one containing 5.00 g of silver nitrate. How many grams of each of the following compounds are present after the reaction is complete? 

sodium carbonate

silver nitrate

silver carbonate

sodium nitrate

Answer 1

First, always write a correctly balanced equation for the reaction in question:

Na₂CO₃(aq) + 2AgNO₃(aq) ==> Ag₂CO₃(s) + 2NaNO₃(aq)

Next, find moles of each reactant and then which, if either, is limiting:

moles Na2CO3 = 7.75 g x 1 mole/106 g = 0.0731 moles

moles AgNO3 = 5.00 g x 1 mole/170 g = 0.0294 moles

Limiting reactant:

0.0731 mol Na2CO3 x 1 mol Ag2CO3/mol Na2CO3 = 0.0731 mol Ag2CO3

0.0294 mol AgNO3 x 1 mol Ag2CO3/2 mol AgNO3 = 0.0147 mol Ag2CO3 = LIMITING REACTANT

Since AgNO3 is limiting, there will be no AgNO3 left after the reaction is complete.

Now to find grams of Na2CO3, Ag2CO3 and NaNO3 present after reaction is complete:

0.0294 mol AgNO3 x 1 mol Na2CO3/2 mol AgNO3 = 0.0147 mol Na2CO3 used

0.0731 mol - 0.0147 mol = 0.0584 mol Na2CO3 remaining x 106 g/mol = 6.19 g Na2CO3 after completion

0.0294 mol AgNO3 x 1 mol Ag2CO3/2 mol AgNO3 = 0.0147 mol Ag2CO3 formed

0.0147 mol Ag2CO3 x 276 g/mol = 4.06 g Ag2CO3 after reaction is complete

0.0294 mol AgNO3 x 2 mol NaNO3/2 mol AgNO3 = 0.0294 mol NaNO2 formed

0.0294 mol NaNO3 x 85.0 g/mol = 2.50 g NaNO3 after reaction is complete