Question

0.60g of hydrogen chloride (HCl) is dissolved in water to make 6.5L of solution. What is the pH of the resulting hydrochloric acid solution?

Answer 1

the dissociation of hydrogen chloride is so large (i.e. a strong acid) that we say that a sample is fully ionized when mixed with water.

you should write a dissociation equation for the reaction, but it's not essential to solving the problem.

After, convert to 0.6 g to moles, from the stoichiometric ratio of the dissociation reaction you'll see that \(H^+:HCl\) is 1:1.

so the moles of HCl are equal to the moles of \(H^+\), now find the molarity of \(H^+\), then use: \(pH=-log[H^+]\) to find the pH.