Chemistry: The Central Science (13th Edition)

$pH \approx 2.876$
1. Find the molar mass of $HClO_3$: H: 1 x 1 = 1 Cl: 1 x 35.5 = 35.5 O: 3 x 16 = 48 1 + 35.5 + 48 = 84.5g/mol 2. Calculate the nº of moles, and the concentration of the solution. nº of moles = mass $\div$ molar mass nº of moles = 0.225 $\div$ 84.5 nº of moles $\approx$ 2.66 $\times$ $10^{-3}$ concentration = nº of moles $\div$ volume(L) $C = \frac{2.66\times10^{-3}}{2}$ $C = 1.33 \times 10^{-3}M (HClO_3)$ 3. Because $(HClO_3)$ is a strong base, and has 1 $H$: $[HClO_3] = [H^+]$ $1.33 \times 10^{-3} = [H^+]$ 4. Calculate the pH: $pH = -log[H^+]$ $pH = -log(1.33\times10^{-3})$ $pH \approx 2.876$