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Two samples of the same gas, at temperatures T1 and T2 where T2 > T1, have the Maxwell–Boltzmann distributions of kinetic energy shown. Which diagram is correct? A. Diagram A B. Diagram B C. Diagram C D. Diagram D
Menthol, used in medicinal rubs, has several chiral carbon atoms in its ring, which is numbered below. Draw circles around two chiral carbon atoms in this structure.
A pharmaceutical chemist has a reference sample of the desired enantiomer of a chiral drug. Explain how a polarimeter can help establish whether a newly prepared sample contains that enantiomer.
50.0 cm3 of copper(II) sulfate solution of concentration 0.200 mol dm−3 is placed in an insulated cup. Excess zinc powder is added and the mixture is stirred. The maximum temperature increase is 10.4 °C.…
Potassium chlorate(V) was heated and the volume of oxygen collected was measured against time. The dotted line shows the result without a catalyst. The experiment is repeated at the same temperature with the same mass of potassium chlorate(V) and with…
Some antacid tablets contain aluminium hydroxide. Write an equation for the neutralization reaction between aluminium hydroxide and stomach acid (hydrochloric acid).
A liquid medicine is buffered with carbonate ions and hydrogencarbonate ions. It contains 0.0120 mol dm−3 carbonate ions and 0.0300 mol dm−3 hydrogencarbonate ions. Ka (hydrogencarbonate ion) = 4.80 × 10−11.…
The rate constant, k, of a reaction was measured at several temperatures. A graph of ln k against 1/T (with T in kelvin) is a straight line with a gradient of −5.2 × 103 K.…
The reaction between hydrogen and iodine monochloride has the overall equation H2(g) + 2 ICl(g) → I2(g) + 2 HCl(g) It proceeds by a two-step mechanism. H2 + ICl → HI + HCl (slow step) HI + ICl → I2 + HCl (fast step) What is the rate…
Ammonia dissolves in water as shown in the equation below. What will happen if the temperature of the solution is increased? NH3(g) + H2O(l) ⇌ NH4+(aq) + OH−(aq) ΔH⊖ = −31 kJ mol−1 A. The equilibrium shifts to the left…