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Aluminium sulfate reacts with barium chloride solution to form a precipitate of barium sulfate and an aqueous solution of aluminium chloride. Al2(SO4)3(aq) + BaCl2(aq) → AlCl3(aq) + BaSO4(s) What is the ratio of the coefficients of barium chloride to…
A sample of chalk is dissolved in acid and titrated with EDTA solution, represented as H2X2−. The titration requires 18.4 cm3 of 0.250 mol dm−3 EDTA. What is the mass of calcium carbonate, CaCO3, in the sample?…
Which of these changes will increase the time taken for this reaction to go to completion? Zn(s) + H2SO4(aq) → ZnSO4(aq) + H2(g) A. Increase the temperature B. Increase the concentration of H2SO4 C. Use powdered zinc instead of zinc granules D.…
Sodium azide, NaN3 (Mr = 65.0), decomposes on heating to form sodium and nitrogen gas. 2 NaN3(s) → 2 Na(s) + 3 N2(g) What volume of nitrogen is produced from 26.0 g of sodium azide at STP? A. 6.05 dm3 B. 9.08 dm3…
Which changes would make the initial rate higher when 50 cm3 of 1.0 mol dm−3 hydrochloric acid reacts with excess marble chips? CaCO3(s) + 2 HCl(aq) → CaCl2(aq) + H2O(l) + CO2(g) I. Raising the temperature by 10 K II. Using 100 cm3 of 1.0 mol…
Which change would shift the position of this equilibrium towards the products? H2(g) + I2(g) ⇌ 2 HI(g) ΔH = −9 kJ mol−1 A. Increase pressure B. Decrease pressure C. Increase temperature D. Decrease temperature
Which statements describe the activation energy of a reaction? I. The minimum energy that colliding particles must have in order to react II. The energy difference between the reactants and the transition state on an energy profile III. The energy difference…
The reaction between nitrogen dioxide and fluorine has the overall equation: 2 NO2(g) + F2(g) → 2 NO2F(g) The reaction follows the energy profile shown: Two mechanisms are suggested: Which suggested mechanism is consistent with the energy profile? A. X…
What can be deduced about this equilibrium reaction from these data? A(g) + B(g) ⇌ 2 C(g) A. It is an exothermic reaction and [products] < [reactants] at equilibrium. B. It is an endothermic reaction and [products] < [reactants] at equilibrium. C. It…
What is the equilibrium constant expression for the forward reaction? 2 SO2(g) + O2(g) ⇌ 2 SO3(g) A. B. C.…