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Two gases react very slowly even at 900 K and a high pressure. Which best explains the low rate of reaction? A. The frequency of collisions between the molecules is low B. A high fraction of the collisions has the correct orientation C. The reaction is…
Identify one absorption range in the IR spectrum of propanoic acid that is not present in the IR spectrum of propan-1-ol. Use section 20 of the data booklet.
A sample is known to be either propan-1-ol or propanoic acid. Its 1H NMR spectrum is shown. (i) Deduce, giving a reason, whether the sample is propan-1-ol or propanoic acid. Use section 21 of the data booklet. (ii) Predict, giving a reason, the splitting…
Which statement is correct for the Arrhenius equation? A. As the temperature increases, the value of increases. B. At a given temperature, k increases as Ea increases. C. A is the minimum…
Paracetamol and phenacetin are two analgesics with similar structures. Predict, giving a reason, which of the two compounds is more soluble in water.
Excess zinc granules react with 40.0 cm3 of hydrochloric acid of concentration 1.00 mol dm−3 at 25 °C. The volume of hydrogen collected was measured over time and curve I was obtained. The experiment is repeated at the same…
The equilibrium constant for the reaction below is Kc = 280 at 700 K. 2 SO2(g) + O2(g) ⇌ 2 SO3(g) What is the value of the equilibrium constant at 700 K for the following reaction? 6 SO3(g) ⇌ 6 SO2(g) + 3 O2(g) A. B.…
Chloramphenicol is an antibiotic. A molecule of chloramphenicol contains two chiral carbon atoms. Identify the two chiral centres by marking each with an asterisk on the structure.
The graph shows plots of ln k against for two reactions, X and Y. Both lines are extended to the vertical axis. Considering the Arrhenius equation , which combination is correct for reactions X and Y?…
The equilibrium constant for the reaction below is Kc = 4.5 × 10−31 at 298 K. Which combination is correct? N2(g) + O2(g) ⇌ 2 NO(g) A. products are favoured and ΔG is positive B. products are favoured and ΔG is negative C.…