1. A student used a pH meter to measure the pH of different samples of water at 298 K.
(a) Use the data in the table to identify the most acidic water sample.
(b) Calculate the percentage uncertainty in the measured pH of the rain water sample.
(c) Determine the ratio of [H+] in bottled water to that in rain water.
(d) The acidity of non-polluted rain water is caused by dissolved carbon dioxide. State an equation for the reaction of carbon dioxide with water.
2. The graph below shows pressure and volume data collected for a sample of carbon dioxide gas at 330 K.
(a) Draw a best-fit curve for the data on the graph.
(b) Deduce the relationship between the pressure and volume of the sample of carbon dioxide gas.
(c) Use the data point labelled X to determine the amount, in mol, of carbon dioxide gas in the sample.
3. Graphite has a layered structure of carbon atoms. A section of the structure is shown below.
(a) Explain why the distance between adjacent carbon atoms within a layer is shorter than the distance between layers.
(b) Graphite is used as a lubricant. Discuss two other uses of graphite with reference to its layered structure.
4. The open-chain structure of D-fructose is shown below.
(a) State the names of two functional groups in D-fructose.
(b) Deduce the empirical formula of D-fructose.
(c) Calculate the percentage composition by mass of D-fructose.
(d) State a balanced equation for the complete combustion of D-fructose.