Question

Use the provided concentrations and volumes to calculate the moles of each reactant.

Equation: Cu(NO3)2 + 2NaHCO3 = CuCO3 + H2O + CO2 + 2NaNO3

75mL of a 1.0 M NaHCO3 solution
15mL of a 1.0 M Cu(NO3)2 solution

1. Moles of Cu(NO3)2 used
2. Moles of NaHCO3 used
3. Which reactant is limiting?
4. How many moles of CuCO3 can actually form from the amount of starting materials used?
5. Calculate the molar mass and theoretical yield of CuCO3 (mass in g).

Answer 1

Equation: Cu(NO3)2 + 2NaHCO3 = CuCO3 + H2O + CO2 + 2NaNO3

that means 1 mole of Cu(NO3)2 will react with 2 moles of NaHCO3 to produce 1 mole of CuCO3

1000ml of 1M solution of any compound contain 1 mole of that compound.

So, 75 ml of 1(M) of NaHCO3 solution contain ( 75/ 1000 )= 0.075 mole of NaHCO3

So, 15 ml of 1(M) of Cu(NO3)2 solution contain ( 15/ 1000 )= 0.015 mole of Cu(NO3)2

Limiting reactant in a chemical reaction is the substance that is totally consumed when the chemical reaction is complete. The amount of product formed is limited by this limiting reactant.

Here, Cu(NO3)2 will be the limiting reactant because 0.015 mole of Cu(NO3)2 will react with 0.03 mole of NaHCO3 to produce 0.015 mole of CuCO3.

Answer 1:  0.015 mole of Cu(NO3)2 used in this reaction

Answer 2:  0.03 mole of NaHCO3 used in this reaction

Answer 3: Cu(NO3)2 will be the limiting reactant

Answer 4: 0.015 mole of CuCO3 will formed from the used starting materials

Answer 5: Molar mass of CuCO3 is 221.116. So theoritical yield of CuCO3 is (0.015 x 221.116) g = 3.317 g