Final answer:
To calculate the number of moles of HCl required to give a pH of 2.10 in a 5.0 L solution, we can use the equation pH = -log[H+]. The pH scale is logarithmic and a pH of 2.10 represents a highly acidic solution. By calculating the molarity (M) of HCl and using the equation moles = M x V, we can determine that approximately 0.03971 moles of HCl are required.
Step-by-step explanation:
To calculate the number of moles of HCl required to give a pH of 2.10 in a 5.0 L solution, we first need to understand the relationship between pH and concentration of HCl. The pH scale is a logarithmic scale that measures the acidity or alkalinity of a solution. A pH of 2.10 indicates a highly acidic solution. In order to calculate the number of moles of HCl, we can use the equation:
pH = -log[H+]
Since the pH of 2.10 represents a concentration of [H+] or [H3O+] in the solution, we can calculate the molarity (M) of HCl using the equation:
M = [H+]
Now we can calculate the number of moles:
moles = M x V
moles = [HCl] x volume
moles = [HCl] x 5.0 L
To find the required moles of HCl, we substitute the concentration and solve:
moles = 10^(-pH) x 5.0 L
moles = 10^(-2.10) x 5.0 L
moles = 0.007943 x 5.0 L
moles = 0.03971
Therefore, the number of moles of HCl required to give a pH of 2.10 in a 5.0 L solution is approximately 0.03971 moles.