Q4. lodide ions are oxidised to iodine by hydrogen peroxide in acidic conditions. H₂O₂(aq) + 2H+(aq) + 21-(aq) → 1₂(aq) + 2H₂O(l) The rate equation for this reaction can be written as rate = k [H₂O₂] [-]³ [H*]c In an experiment to determine the order with respect to H*(aq), a reaction mixture is made containing H*(aq) with a concentration of 0.500 mol dm-3 A large excess of both H₂O₂ and 1- is used in this reaction mixture so that the rate equation can be simplified to rate = k₁ [H*]c (a) Explain why the use of a large excess of H₂O2 and I means that the rate of reaction at a fixed temperature depends only on the concentration of H*(aq). (b) Samples of the reaction mixture are removed at timed intervals and titrated with alkali to determine the concentration of H*(aq). State and explain what must be done to each sample before it is titrated with alkali.

The reaction, 2 NO(g) + Cl2(g) --> 2 NOCl(g), proceeds through the following mechanism:   NO(g) + Cl2(g) --> NOCl2(g)NOCl2(g) + NO(g) --> 2 NOCl(g) The second step of this mechanism is rate-determining (slow). What would the rate law for this reaction be if the first step were rate-determining?

Under certain conditions the rate of this reaction is zero order in ammonia with a rate constant of 0.0076 M•s *: 2 NH, (g) → N2 (g) + 3 H, (g) Suppose a 5.0 L flask is charged under these conditions with 500. mmol of ammonia. How much is left 3.0 s later? You may assume no other reaction is important. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits. x10

Under certain conditions the rate of this reaction is zero order in dinitrogen monoxide with a rate constant of 0.0085 M·s : 2 N,0 (g) → 2 N2 (g)+O, (g) Suppose a 5.0L flask is charged under these conditions with 500. mmol of dinitrogen monoxide. How much is left 3.0 s later? You may assume no other reaction is important. olo Be sure your answer has a unit symbol, if necessary, and round it to 2 significant digits. Ar x10

Under certain conditions the rate of this reaction is zero order in dinitrogen monoxide with a rate constant of 0.0075 M's : 2 N,0 (g) → 2 N2 (g) + O, (g) Suppose a 350. mL flask is charged under these conditions with 100. mmol of dinitrogen monoxide. After how much time is there only 50.0 mmol left? You may assume no other reaction is important. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits. x10

The rate law for the reaction 2NO(g) + 2H₂(g) → N₂(g) +2H₂O(g) is rate = k[NO]²[H₂] If the rate of reaction is 7.00 x 10-3 mol L¹s ¹ when the concentrations of NO and H₂ are both 1.8 x 106 mol L-1, what is the value of the rate constant and what are the units for the rate constant?, k= i 3.8 x 1015 L³ mol-3 s-1 L² mol-² 5-1 S-1 OL mol-¹ s-1 mol L-15-1 e Textbook and Media Hint Save for Later Attempts: 3 of 15 used Submit Answer

You have a reaction: A + B --> C The reaction is first order with respect to A and 2nd order with respect to B.  If 1.2 mol of A is mixed with 2.5 mol of B to make a 1.000 L solution and the rate of the reaction is 1.9 M/s, what is the rate constant (k)? Your answer should have no units.

Hemoglobin molecules in blood bind oxygen and carry it to cells, where it takes part in metabolism. The binding of oxygen hemoglobin(aq) + O2(aq) – → hemoglobin · O2(aq) is first order in hemoglobin and first order in dissolved oxygen, with a rate constant of 4 × 107 L mol¯1s¯1. Calcu- late the initial rate at which oxygen will be bound to hemo- globin if the concentration of hemoglobin is 2 x 10-9 M and that of oxygen is 5 × 10-s M.

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Under certain conditions the rate of this reaction is zero order in hydrogen lodide with a rate constant of 0.0038 M's ': 2 HI(g) H,(g)+1,(g) Suppose a 4.0L flask is charged under these conditions with 100, mmol of hydrogen lodide. After how much time is there only 50.0 mmol left? You may assume no other reaction Is important. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits.