A chemist needs a HCl solution with a molarity of less than 0.400 M for an experiment. To find out if a sample of HCl solution can be used in the lab, the chemist performs a titration to neutralize 59.2 mL of the HCl with 45 mL of 0.400 M NaOH. Based on the results, will the acid be useful for the chemist’s experiment?
mLHCl x MHCl = mLNaOH x MNaOH
Substitute and solve for MHCl and compare with 0.400.
Of course you need not do a calculation. If the NaOH is 0.400 and it takes more HCl to neutralize the NaOH you know HCl is weaker than NaOH or HCl < 0.400M
To determine if the acid is useful for the chemist's experiment, we need to calculate the concentration of the HCl solution.
The balanced chemical equation for the reaction between HCl (acid) and NaOH (base) is:
HCl + NaOH → NaCl + H2O
From the balanced chemical equation, we can see that 1 mole of HCl reacts with 1 mole of NaOH to produce 1 mole of NaCl and 1 mole of water.
First, let's calculate the number of moles of NaOH used:
Number of moles of NaOH = concentration of NaOH × volume of NaOH solution
= 0.400 M × 0.045 L
= 0.018 moles
Since the stoichiometry of the reaction is 1:1 between HCl and NaOH, the number of moles of HCl in the 59.2 mL solution is also 0.018 moles.
Now, let's calculate the concentration of the HCl solution:
Concentration of HCl = moles of HCl ÷ volume of HCl solution
= 0.018 moles ÷ 0.0592 L
≈ 0.304 M
The concentration of the HCl solution is approximately 0.304 M, which is less than the required 0.400 M for the experiment. Therefore, based on the results of the titration, the acid will not be useful for the chemist's experiment.