31 6.3 The pH Scale

Practice questions

1. 1. 1. What is pH?
         1. 1. pH is the negative logarithm of $[\mathrm{OH}{\phantom{A}}^{-}]$
            2. pH is the negative logarithm of $[\mathrm{H}{\phantom{A}}^{+}]$
            3. pH is the logarithm of $[\mathrm{H}{\phantom{A}}^{+}]$
            4. pH is the logarithm of $[\mathrm{OH}{\phantom{A}}^{-}]$
      2. What is the pH range for an acidic solution?
         1. 1. $\mathrm{pH}=7$
            2. $\mathrm{pH}<7$
            3. $\mathrm{pH}>7$
            4. $\mathrm{pH}=14$
      3. What is the pH range for a basic solution?
         1. 1. $\mathrm{pH}=7$
            2. $\mathrm{pH}<7$
            3. $\mathrm{pH}>7$
            4. $\mathrm{pH}=1$
      4. What is $[\mathrm{H}{\phantom{A}}^{+}]$
         1. 1. $1.0\times {10}^{-7}M$
            2. $1.0\times {10}^{-14}M$
            3. $1.0\times {10}^{-1}M$
            4. $1.0\times {10}^{-8}M$
      5. What is the pH of a solution when $[\mathrm{H}{\phantom{A}}^{+}]$ is $3.44\times {10}^{-4}M?$
         1. 1. pH of 3.6
            2. $1.0\times {10}^{-4}M$
            3. pH of 4
            4. pH of 8
      6. What is the pH of a solution when $[\mathrm{OH}{\phantom{A}}^{-}]$ is $6.22\times {10}^{-7}M?$
         1. 1. pH of 0.79
            2. pH of 2
            3. pH of 7.79
            4. pH of 6
      7. What is the pOH of a solution when $[\mathrm{H}{\phantom{A}}^{+}]$ is $3.44\times {10}^{-4}M?$
         1. 1. pOH of 1.89
            2. pOH of 10.54
            3. pOH of 3.46
            4. pOH of 0.54
      8. What is the pOH of a solution when $[\mathrm{OH}{\phantom{A}}^{-}]$ is $6.22\times {10}^{-7}M?$
         1. 1. pOH of 3.46
            2. pOH of 7.79
            3. pOH of 6.21
            4. pOH of 7
      9. If a solution has a pH of $0.77$, what is its pOH, $[\mathrm{H}{\phantom{A}}^{+}]$, and $[\mathrm{OH}{\phantom{A}}^{-}]$?
      10. If a solution has a pOH of $13.9$, what is its pH, $[\mathrm{H}{\phantom{A}}^{+}]$, and $[\mathrm{OH}{\phantom{A}}^{-}]$?

Answers

1. b
2. b
3. c
4. a
5. a
6. c
7. b
8. c
9. $pOH=13.23$, $[{\mathrm{H}}^{+}]=1.70\times {\phantom{A}}_{10}{\phantom{A}}^{-1}\mathrm{M}$, $[{\mathrm{OH}}^{\text{-}}]=5.89\times {\phantom{A}}_{10}{\phantom{A}}^{-14}$
10. $pH=0.91$, $[{\mathrm{H}}^{+}]=8.13\times {\phantom{A}}_{10}{\phantom{A}}^{-14}M$, $[{\mathrm{OH}}^{\text{-}}]=0.12\mathrm{M}$