Question

When 13.91 mL of HCl of unknown concentration (but less than that of the base) are reacted with 15.00 mL of 3.161 M NaOH, 1.47 kJ of heat are released. What is the molarity of the HCl solution?

Answer 1

This problem is providing the volume of HCl as 13.91 mL and the volume and concentration of NaOH as 15.00 mL and 3.161 M, respectively. Thus, the concentration of the acid is required and found to be 3.409 M according to the following:

Neutralization reactions:

In chemistry, neutralization reactions between acids and bases are used in order to produce a neutral product (salt) for different purposes. Thus, since this problem is about the reaction between HCl and NaOH, we can write:

$HCl+NaOH\rightarrow NaCl+H_2O$

Where the acid and the base are in a 1:1 mole ratio; which means we can set the following up:

$M_{acid}V_{acid}=M_{base}V_{base}$

Hence, we can solve for the molarity (concentration) of the acid as shown below:

$M_{acid}=\frac{M_{base}V_{base}}{V_{acid}}$

And finally plug in the initial data to obtain the result:

$M_{acid}=\frac{15.00mL*3.161M}{13.91mL}\\ \\M_{acid}=3.409M$

Learn more about neutralization reactions: https://brainly.com/question/4612545