AQA Physical Chemistry 2 Welcome to your AQA Physical Chemistry 2 When sulphur dioxide is formed from sulphate ions, what is the change in oxidation number of sulphur? +6 to +4 +4 to+6 No change +4 to 0 Which of the following orders is correct such that the first compound has the most negative lattice enthalpy and the last has the least? MgO, BaCl<sub>2</sub>, KCl KCl, BaCl<sub>2</sub>, MgO BaCl<sub>2</sub>, MgO, KCl KCl, MgO, BaCl<sub>2</sub> What causes a difference in theoretical and Born Harber lattice enthalpies? Polaisation of negative ion 100% ionic character of a compound The spherical shape of ions All of the options What can be said about entropy change when solid ammonium chloride decomposes to ammonia and hydrogen chloride gas? Positive Negative Remains the same Unpredictable The rate of a reaction is not affected by a change in concentration of a reactant X. What is the order of the reaction with respect to X? Zero 1st 2nd Order cannot be determined by the given information A reaction is first order with respect to reactant X and second order with respect to reactant Y. If the concentration of X is doubled and the concentration of Y is tripled, by what factor has the rate increased? 18 times 6 times 12 times 8 times The reaction rate increases 9 times by tripling the concentration of reactant A. What is the order of the reaction with respect to A? 2nd 1st Zero 3rd A mixture has a total pressure 2 kPa, contains 0.2 mol of nitrogen and has 0.6 mol of oxygen. What is the partial pressure of nitrogen gas in the mixture? 0.5 1.5 0.75 0.25 Which of the following do not affect the value of Kp?I. TemperatureII. PressureIII. Concentration II and III only III only II only I and III only What is the effect of increasing Kp on the equilibrium of a reaction? Product yield increases Product yield decreases Kp does not affect the equilibrium The activation energy decreases What material is used as an electrode of a standard hydrogen electrode (SHE)? Platinum Silver Copper Titanium Which of the following statements is true? More negative half cells oxidise More negetive half cells reduce Powerful oxidising agents have lower oxidation numbers The EMF of a cell is the same as the EMF of the reduced half of the cell Which of the following affect the Ecell?I. ConcentrationII. Temperature I and II I only II only None of them Which of the following statements is incorrect? Kw is constant at all temperatures Increasing the temperature causes a decrease in the pH of water Kw is derived from Kc The unit of Kw is mol2/dm6 Assuming complete dissociation, what is the pH of 0.5M potassium hydroxide (KOH)? 13.7 13 10.6 14 What is acidic buffer is made of? A solution of weak acid and its salt A solution of a salt of a weak acid A weak acid A weak base Time is Up!