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Which of the following could be used to follow the progress of the reaction between calcium carbonate and dilute nitric acid? CaCO3(s) + 2 HNO3(aq) → Ca(NO3)2(aq) + H2O(l) + CO2(g) I. A balance recording the mass of the open flask and its contents II. A…
30 cm3 of butane was completely burned in 250 cm3 of oxygen according to the following equation. 2 C4H10(g) + 13 O2(g) → 8 CO2(g) + 10 H2O(l) What volume of oxygen remains unreacted, measured at the original conditions? A. 55…
The rate of the reaction between propanone and iodine in acidic solution was measured at a fixed concentration of the acid catalyst. CH3COCH3(aq) + I2(aq) → CH3COCH2I(aq) + HI(aq) What is the overall reaction order? A. Zero order B. First order C.…
The table shows how the initial rate of the reaction between X and Y depends on the concentrations of the reactants. What is the order of reaction with respect to each reactant? A. X: 1, Y: 1 B. X: 2, Y: 1 C. X: 1, Y: 2 D. X: 2, Y: 0
The Maxwell–Boltzmann distribution below was obtained for a sample of gas at temperature T1. The activation energy of a reaction is marked as Ea. Which graph shows the distribution for the same sample at a higher temperature, T2, together…
Which statement about the rate constant, k, of an elementary reaction is correct? A. k increases when the temperature is raised, whether the reaction is exothermic or endothermic. B. k decreases when the temperature is raised for exothermic reactions. C. k…
A reaction has the rate equation below. What are the units of the rate constant k? rate = k[A]2[B][C]0 A. s−1 B. mol−1 dm3 s−1 C. mol−2 dm6 s−1 D.…
The gas-phase decomposition below has reached equilibrium in a sealed vessel: PCl5(g) ⇌ PCl3(g) + Cl2(g) ΔH⊖ = +88 kJ mol−1 The pressure is then changed. Which row pairs the change correctly with the direction in which the…
The following system is at equilibrium. H2(g) + I2(g) ⇌ 2 HI(g) K = 54 What is the value of the equilibrium constant, K, for the reaction 2 HI(g) ⇌ H2(g) + I2(g)? A. −54 B. C. D.
Iron(III) ions and thiocyanate ions form a deep red complex ion in aqueous solution. Fe3+(aq) + SCN−(aq) ⇌ [Fe(SCN)]2+(aq) Which of the following correctly predicts the effect of a change on this equilibrium? A. Adding iron(III) nitrate solution…