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The reaction 2 P → S + T was studied by measuring the initial rate at different initial concentrations of P. Which graph shows that the reaction is first order with respect to P? A. Graph A B. Graph B C. Graph C D. Graph D
A mixture of 1 mol of nitrogen and 1 mol of oxygen is left to reach equilibrium at 25 °C. N2(g) + O2(g) ⇌ 2 NO(g) K = 4.5 × 10−31 at 25 °C Which relationship holds in the equilibrium mixture? A. [NO] ≪ [N2] B.…
Which statement explains why a chemical equilibrium is described as dynamic? A. The forward and reverse reactions continue to take place at equal rates. B. The concentrations of the reactants and products keep changing until the reaction stops. C. The position…
Sulfur dioxide and oxygen react reversibly: 2 SO2(g) + O2(g) ⇌ 2 SO3(g) At a certain temperature the equilibrium constant is K = 4.0. A mixture at this temperature has the following concentrations, in mol dm−3: [SO2] = 0.50,…
Nitrogen reacts with hydrogen to form ammonia. N2(g) + 3 H2(g) ⇌ 2 NH3(g) A mixture of 1.50 mol of N2(g) and 4.20 mol of H2(g) was placed in a 1.00 dm3 container at a certain temperature. At equilibrium the mixture contained…
An aqueous solution at 298 K has a pH of 9.20. Kw = [H+][OH−] = 1.00 × 10−14 at 298 K What is the hydroxide ion concentration of the solution, in mol dm−3? A. 6.31 × 10−10 B. 1.58 × 10−9 C.…
In which reaction does water behave as a Brønsted–Lowry acid? A. H2O(l) + HCl(g) → H3O+(aq) + Cl−(aq) B. H2O(g) + SO3(g) → H2SO4(l) C. 2 H2O(l) → 2 H2(g) + O2(g) D. H2O(l) + NH3(aq) → NH4+(aq) + OH−(aq)
Which of these aqueous solutions has the highest pH? A. 0.10 mol dm−3 HCl B. 1.0 mol dm−3 NH3 C. 0.10 mol dm−3 KOH D. 1.0 mol dm−3 KOH
Which aqueous solution has the highest pH? A. 0.010 mol dm−3 KNO3 B. 0.010 mol dm−3 NH4NO3 C. 0.010 mol dm−3 CH3COONa D. 0.010 mol dm−3 NaHSO4
Which row identifies the oxidizing agent and the reducing agent in the reaction below? 3 Cu(s) + 2 NO3−(aq) + 8 H+(aq) → 3 Cu2+(aq) + 2 NO(g) + 4 H2O(l) A. Oxidizing agent: Cu, reducing agent: NO3− B. Oxidizing agent: NO3−, reducing…