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A reaction proceeds by the following mechanism. Step 1: NO2 + NO2 → NO3 + NO (slow) Step 2: NO3 + CO → NO2 + CO2 (fast) Which statement is correct about the reaction? A. The overall equation for the reaction is 2 NO2 → NO3 + NO B.…
Which two species form a conjugate acid-base pair in this reaction? HCOOH(aq) + NH3(aq) ⇌ HCOO−(aq) + NH4+(aq) A. HCOOH and HCOO− B. HCOOH and NH3 C. NH3 and HCOO− D. HCOOH and NH4+
Compounds M and N both contain a 4-methoxyphenyl group, shown at the left of each structure. Their side chains are −CH2CH2COOH in M and −C(CH3)2OH in N. Predict the number of signals and the relative areas you would expect in the 1H NMR…
4-Phenylbutan-2-one is made by oxidizing 4-phenylbutan-2-ol. A sample of the product is contaminated with some unreacted alcohol. The infrared spectra of the pure ketone and of the pure alcohol are shown. Deduce, giving two reasons, which spectrum belongs to…
Which graph of rate of reaction against concentration of the reactant is correct for a reaction that is second order with respect to that reactant? A. Graph A B. Graph B C. Graph C D. Graph D
Which method can be used to distinguish between nitric acid, HNO3(aq), and ethanoic acid, CH3COOH(aq), of equal concentration? A. measuring the volume of sodium hydroxide solution of known concentration needed to neutralize 20.0 cm3…
Which pair of changes will both shift the position of equilibrium to the left? CH4(g) + H2O(g) ⇌ CO(g) + 3 H2(g) ΔH = +206 kJ mol−1 A. Decrease the temperature and increase the pressure B. Increase the temperature and increase…
At 298 K the pKa of methanoic acid is 3.75 and the pKa of ethanoic acid is 4.76. Which statement is correct for solutions of these acids with the same concentration? A. Ethanoic acid is a stronger acid than methanoic…
1.50 mol of NO and 0.80 mol of O2 are mixed in a 2.0 dm3 container and allowed to reach equilibrium at a certain temperature. 2 NO(g) + O2(g) ⇌ 2 NO2(g) There was 1.20 mol of NO2 present in the container at equilibrium. What…
Which combination would produce a buffer solution? A. 50 cm3 of 1.0 mol dm−3 NH3(aq) and 50 cm3 of 1.0 mol dm−3 HCl(aq) B. 25 cm3 of 1.0 mol dm−3…