233,960 views
24 votes
24 votes
Determine the limiting reagent in the following equation for the production of salt and determine the amount of NaCl produced and the mass of excess reagent. (I - 10 marks)

100g 100g
NaHCO3 + HCl —> NaCl + H2O + CO2

User Ialiashkevich
by
2.8k points

1 Answer

14 votes
14 votes

Answer:

Limiting Reagent: NaHCO₃

Amount of NaCl: 69.6 g NaCl

Mass of Excess Reagent: 56.6 g HCl

Step-by-step explanation:

To find the mass of NaCl, you need to (1) convert mass reactant to moles reactant (via molar mass), then (2) convert moles reactant to moles NaCl (via mole-to-mole ratio from equation coefficients), and then (3) convert moles NaCl to mass NaCl (via molar mass).

Molar Mass (NaHCO₃):

22.990 g/mol + 1.008 g/mol + 12.011 g/mol + 3(15.998 g/mol)

Molar Mass (NaHCO₃): 84.003 g/mol

Molar Mass (HCl): 1.008 g/mol + 35.453 g/mol

Molar Mass (HCl): 36.461 g/mol

Molar Mass (NaCl): 22.990 g/mol + 35.453 g/mol

Molar Mass (NaCl): 58.443 g/mol

100 g NaHCO₃ 1 mole 1 mole NaCl 58.443 g
------------------------ x ------------------ x --------------------------- x ---------------- =
84.003 g 1 mole NaHCO₃ 1 mole

= 69.6 g NaCl

100 g HCl 1 mole 1 mole NaCl 58.443 g
---------------- x ------------------ x ----------------------- x ---------------- =
36.461 g 1 mole HCl 1 mole

= 160 g NaCl

Since NaHCO₃ results in the smaller amount of product, it is the limiting reagent. In other words, it is used up before the HCl has the chance to completely react. Therefore, the actual amount of NaCl produced is 69.6 grams.

To find the mass of the excess reagent, you need to calculate the amount of HCl actually used in the reaction. Then, you need to subtract that value from the total amount of HCl.

69.6 g NaCl 1 mole 1 mole HCl 36.461 g
--------------------- x ------------------ x ----------------------- x ---------------- =
58.443 g 1 mole NaCl 1 mole

= 43.4 g HCl

Amount Given - Amount Reacted = Mass Excess

100 g HCl - 43.4 g HCl = 56.6 g HCl

User Emilie
by
2.9k points