Complete the equation to define $K_w$ mathematically. $K_w =\; \ldots\ldots\ldots\ldots\ldots\ldots\ldots\ldots\ldots\ldots$
Two solutions, $V$ and $W$, are given. • $V$ is $\text{HCl}(aq)$. • $W$ is $\text{NaOH}(aq)$. • The concentration of HCl in $V$ matches the concentration of NaOH in $W$. • The pH values of $V$ and $W$ are exactly $11.00$ apart at $298\,\text{K}$. Calculate the concentration of HCl in $V$. concentration of HCl in $V = \;\ldots\ldots\ldots\ldots\ldots\ldots\,\text{mol dm}^{-3}$
Equal amounts of the two solutions $V$ and $W$ are mixed to form solution $X$. Name solution $X$ and give its pH. solution $X$ $\ldots\ldots\ldots\ldots\ldots\ldots$\quad pH $\ldots\ldots\ldots\ldots$
A $1\,\text{cm}^3$ portion of $1.0\,\text{mol dm}^{-3}\,\text{HNO}_3$ is introduced into $100\,\text{cm}^3$ of solution $X$, producing mixture $Y$. A $1\,\text{cm}^3$ portion of $1.0\,\text{mol dm}^{-3}\,\text{KOH}$ is introduced into $100\,\text{cm}^3$ of solution $X$, producing mixture $Z$. Estimate the pH of mixtures $Y$ and $Z$. No calculations are needed. mixture $Y$ $\ldots\ldots\ldots\ldots$\quad mixture $Z$ $\ldots\ldots\ldots\ldots$
$\text{CH}_3\text{CH}_2\text{COOH}$, $\text{CH}_3\text{CCl}_2\text{COOH}$ and $\text{H}_2\text{SO}_4$ all show acidic behaviour. Suggest the trend in their relative acid strengths. Explain your answer. strongest acid $\ldots\ldots\ldots\ldots$\quad weakest acid $\ldots\ldots\ldots\ldots$ explanation $\ldots\ldots\ldots\ldots\ldots\ldots\ldots\ldots\ldots\ldots$
When concentrated $\text{H}_2\text{SO}_4$ is mixed with water, a sequence of acid-base reactions takes place. Three conjugate acid-base pairs can be picked out from this sequence. Write the formulae for these three conjugate acid-base pairs.
Define partition coefficient, $K_{pc}$.
$5.00\,\text{g}$ of $Q$ is shaken with a mixture made from $100.0\,\text{cm}^3$ of water and $100.0\,\text{cm}^3$ of hexane at $298\,\text{K}$ and left until the concentrations stop changing. Calculate the mass of $Q$ dissolved in the water.
A sample of $Q$ is shaken with a different water–hexane mixture and left until the concentrations no longer change. The mass of $Q$ dissolved in each solvent is then the same. Use the $K_{pc}$ value to suggest possible values for the volumes of water and hexane used.
$Q$ dissolves more readily in hexane than in water. It is suggested that $Q$ is one of KCl, $\text{CH}_3(\text{CH}_2)_4\text{OH}$ or HCOOH. Identify $Q$. Explain your answer.