calculate the molarity of an acetic acid solution if 39.96 mL of the solution is needed to neutralize 136mL of 1.41 M sodium hydroxide. the equation for the reaction is
HC2H3O2(aq) + NaOH(aq) > Na+(aq) + C2H3O2(aq)
+H2O(aq)
To calculate the molarity of the acetic acid solution, you need to use the concept of stoichiometry and the given information from the neutralization reaction.
Here's how you can approach the problem step-by-step:
Step 1: Determine the balanced chemical equation for the reaction.
The balanced equation for the reaction between acetic acid (HC2H3O2) and sodium hydroxide (NaOH) is:
HC2H3O2(aq) + NaOH(aq) → Na+(aq) + C2H3O2-(aq) + H2O(l)
Step 2: Determine the number of moles of NaOH used.
Since the molarity and volume of sodium hydroxide (NaOH) is provided, we can calculate the number of moles NaOH using the formula:
moles = Molarity × Volume (in liters)
Given:
Molarity of NaOH (M1) = 1.41 M
Volume of NaOH used (V1) = 136 mL = 0.136 L
moles NaOH = Molarity × Volume
moles NaOH = 1.41 M × 0.136 L
Step 3: Determine the stoichiometric ratio between NaOH and HC2H3O2.
From the balanced equation, we can see that the stoichiometric ratio between NaOH and HC2H3O2 is 1:1. This means that for every one mole of NaOH, there is one mole of HC2H3O2.
Step 4: Determine the number of moles of HC2H3O2.
Since the stoichiometric ratio is 1:1, the number of moles of HC2H3O2 is also equal to the moles of NaOH used.
moles HC2H3O2 = moles NaOH
Step 5: Determine the volume of the acetic acid solution.
The volume of the acetic acid solution is provided as 39.96 mL = 0.03996 L.
Step 6: Calculate the molarity of the acetic acid solution.
Molarity is defined as the number of moles of solute per liter of solution. To find the molarity (M2) of the acetic acid solution, we can use the formula:
Molarity = Moles of Solute / Volume of Solution (in liters)
Molarity of HC2H3O2 (M2) = moles HC2H3O2 / Volume of HC2H3O2 solution
Substituting the values:
Molarity of HC2H3O2 (M2) = (moles NaOH) / (volume of HC2H3O2 solution)
Molarity of HC2H3O2 (M2) = (moles NaOH) / (0.03996 L)
Finally, substitute the values you obtained in the earlier steps to calculate the molarity of the acetic acid solution.