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Quiz – Strength of acids and bases

Understanding the strength of acids and bases is crucial for predicting their behaviour in chemical reactions and their impact in various applications. Test your ability to identify and differentiate between strong and weak acids and bases with this quiz.

Your turn – strength of acids and bases

  1. The \(\ce{HBr}\) in a \(0.1\textrm{M}\) \(\ce{HBr}\) solution is \(100\%\) dissociated. Calculate the molar concentrations of \(\ce{HBr}\), \(\ce{H3O}^{+}\) and \(\ce{Cl}^{-}\) in the solution.

\(\ce{H3O}^{+}=0.1\textrm{M}\)

\(\ce{Br}^{-}=0.1\textrm{M}\)

\(\ce{HBr}=0\textrm{M}\)

  1. Determine the number of acidic and non-acidic hydrogens present in the following molecules.
    1. \(\ce{HNO3}\)

    \(1\) acidic and \(0\) non-acidic

    1. \(\ce{H2C4H4O4}\) (succinic acid)

    \(2\) acidic and \(4\) non-acidic

    1. \(\ce{NH3}\)

    \(3\) acidic and \(0\) non-acidic

    1. \(\ce{CH4}\)

    \(0\) acidic and \(4\) non-acidic

  1. Use the acid ionisation constants in the table to identify the stronger acid in each acid pair.
Formula \(K_{a}\)
\(\ce{H}_{3}\ce{PO}_{4}\) \(7.5\times10^{-3}\)
\(\ce{HF}\) \(6.8\times10^{-4}\)
\(\ce{HNO}_{2}\) \(4.5\times10^{-4}\)
\(\ce{HCN}\) \(4.9\times10^{-10}\)
\(\ce{H}_{2}\ce{CO}_{3}\) \(4.3\times10^{-7}\)
\(\ce{HCO}_{3}^{-}\) \(5.6\times10^{-11}\)
    1. \(\ce{H3PO4}\) and \(\ce{HNO2}\)

    \(\ce{H3PO4}\)

    1. \(\ce{HCN}\) and \(\ce{HF}\)

    \(\ce{HF}\)

    1. \(\ce{H2CO3}\) and \(\ce{HCO}_{3}^{-}\)

    \(\ce{H2CO3}\)

    1. \(\ce{HNO2}\) and \(\ce{HCN}\)

    \(\ce{HNO2}\)

  1. A \(0.0300\textrm{M}\) of a base is \(7.5\%\) ionised. Calculate the base ionisation constant \(K_{b}\).

\(K_{b}=1.82\times10^{-4}\textrm{M}\)

  1. A \(0.0500\textrm{M}\) of an acid is \(15\%\) ionised. Calculate the acid ionisation constant \(K_{a}\).

\(K_{a}=1.32/times10^{-3}\textrm{M}\)