## Chemistry: The Molecular Science (5th Edition)

1.827g of $HCl$.
1. Use the pH to find the hydronium concentration. $[H_3O^+] = 10^{-pH}$ $[H_3O^+] = 10^{- 1.3}$ $[H_3O^+] = 5.012 \times 10^{- 2}M$ - Since $HCl$ is a strong acid: $[HCl] = [H_3O^+]$ 2. Calculate the number of moles: (HCl) - 1000ml = 1L $n(moles) = concentration(M) * volume(L)$ $n(moles) = 0.05012 * 1$ $n(moles) = 0.05012$ 3. Find the mass value in grams: (HCl) Molar mass (HCl) : 1.01* 1 + 35.45* 1 = 36.46g/mol $mass(g) = mm(g/mol) * n(moles)$ $mass(g) = 36.46 * 0.05012$ $mass(g) = 1.827$