Question

A weighed amount of sodium chloride is completely dissolved in a measured volume of 4.00 M ammonia solution at ice temperature, and carbon dioxide is bubbled in. Assume that sodium bicarbonate is formed util the limiting reagent is entirely used up. the solubility of sodium bicarbonate in water at ice temperature is 0.75 mol per liter. Also assume that all the sodium bicarbonate precipitated is collected and converted quantitatively to sodium carbonate.

Data to be used for calculating the results
-The mass of sodium chloride in (g) is 13.75
-The volume of ammonia solution in (mL) is 36.22

Calculate the following
-How many moles of sodium chloride are present in the original solution?
-How many moles of ammonia are present originally?
-What is the limiting reagent? a)ammonia, b)sodium chloride
-What is the theoretical yield of sodium bicarbonate in grams?
-How many grams of the sodium bicarbonate formed will precipitate from the above volume of solution?
-How many grams of sodium carbonate will be produced from the precipitate?

PLEASE SHOW ALL STEPS THANK YOU!!!

Answer 1

Molecular weights : NaCl =58.5, NH3= 17

moles = mass/ Molecular weight, moles of NaCl =13.75/58.8 =0.230 g/mole

moles of NH3= molarity* volume (L)= 4*36.22/1000 =0.145 moles

the reactino is NaCl+NH3+CO2+H2O----> NaHCO3+ NH4Cl

1mole of NH3 requires 1 mole of NaCl to give 1 mole of NaHCO3

molar ratio of reactants NH3 : NaCl = 1: 1 given ratio = 0.145 : 0.230 = 1: 1.59

so limiting reactant is NH3

theroretical yiled of NaHCO3 =0.145 moles

Molecular weight of NaHCO3= 23+1+48= 84 gm, mass of NaHCO3= 0.145*84= 12.18 gm

solubility of NaHCO3 =0.75 mol/L

1 L dissovles 0.75 moles of NaHCO3

36.22ml =36.22/1000 L =0.03622 L gives 0.03622*0.75 moles of NaHCO3= 0.027165 moles= 0.027165*84 gms=2.28 gm

mass of NaHCO3 precipiated= 12.18- 2.28= 9.9 gm

NaHCO3 when heated gives

2NaHCO3---Na2CO3 +CO2+ H2O

84 gm of NaHCO3 gives 106 gm of Na2CO3 ( molecular weights : NaHCO3= 84 and Na2CO3= 106)

9.9 gm gives 9.9*106/84 gm of Na2CO3= 12.49 gm of Na2CO3