ATP has a molar absorptivity of 15400 L mol-1 cm-1 at 259 nm. An ATP solution of unknown concentration gives an absorbance of 1.9 at 259 nm when placed in a cuvette with a path length of 1 cm. What is the concentration of ATP in the unknown solution? This question is worth 2 marks.

Questions 41 – 43 relate to the following problem: You have a solution of 0.5 mol dm-3 sodium hydroxide. Titration of 125.0 cm3 of this solution required 30 cm3 of a hydrochloric acid solution for complete neutralisation.                                                                                            How many moles of sodium hydroxide were neutralised?

What mass of NaOH do we need to prepare 250 mL of a 3.5 M solution? (Molar mass of NaOH = 40 g/mol)

Which one of the following elements has the highest electronegativity?

The concentration of compound X is measured at different time intervals during the course of a chemical reaction. After plotting a graph of the concentration of X against time, shown below, the points labelled A-E on the graph have the following co-ordinates: A: x = 0 seconds; y = 0 mol L-1 B: x = 8 seconds; y = 0.37 mol L-1 C: x = 15 seconds; y = 0.49 mol L-1 D: x = 23 seconds; y = 0.63 mol L-1 E: x = 30 seconds; y = 0.60 mol L-1   What is the rate of the chemical reaction at point C? This question is worth 3 marks.

Which one of the following statements regarding glucose metabolism is False?

Which of the following statements about reaction kinetics is False?

Which one of the following nitrogenous bases is not found in DNA?

Which of the following phrases correctly completes the sentence ‘Chemical reactions occur spontaneously……..’

Which one of the following statements about bonding is False?