Question

If 39.85 mL of HCl is required to titrate 2.295 g of Na₂CO₃ according to the following equation, what is the concentration (mol/L) of the HCl solution?

Na₂CO₃(aq) + 2HCl(aq) + 2NaCl(aq) + CO₂(g) + H₂O(1)
Concentration= answer in M

Answer 1

To find the concentration of the HCl solution, calculate the number of moles of HCl that reacted with Na₂CO₃. Substitute the values into the formula moles = volume × concentration and solve for the concentration of HCl. The final concentration is calculated using the balanced chemical equation and the mass of Na₂CO₃.

Step-by-step explanation:

To find the concentration of the HCl solution, we need to calculate the number of moles of HCl that reacted with Na₂CO₃. We can use the formula:

moles = volume × concentration

First, convert the volume of HCl used from mL to L: 39.85 mL = 0.03985 L

Next, substitute the values into the formula:

moles of HCl = 0.03985 L × concentration of HCl

Solve for the concentration of HCl:

concentration of HCl = moles of HCl / 0.03985 L

Finally, substitute the moles of HCl calculated from the balanced chemical equation:

concentration of HCl = 2.295 g Na₂CO₃ × (1 mol Na₂CO₃ / molar mass of Na₂CO₃) × (2 mol HCl / 1 mol Na₂CO₃) / 0.03985 L

Simplify the expression to get the final answer. The concentration of the HCl solution is ____ M.