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Ephedrine is a decongestant found in some cold remedies. Its structure is shown. Deduce which two carbon atoms in a molecule of ephedrine are chiral. For each of them, state the four different atoms or groups bonded to it.
Which pair of colliding species has the highest probability that a collision with sufficient energy also has the proper orientation? A. CH3Cl + OH− B. Br ⋅ + Br ⋅ C. C2H4 + HBr D. CH4 + Cl ⋅
The reaction between nitrogen dioxide and carbon monoxide, NO2 + CO → NO + CO2, is proposed to take place by the following mechanism. Step 1 (slow): 2 NO2 → NO3 + NO Step 2 (fast): NO3 + CO → NO2 + CO2 What is the order of reaction with…
Which proposed mechanism for the following reaction is consistent with the rate equation? H2(g) + 2 ICl(g) → I2(g) + 2 HCl(g) rate = k[H2][ICl] A. One step: H2 + 2 ICl → I2 + 2 HCl B. Step 1 (slow): H2 + ICl → HI + HCl;…
Each option shows a graph of the concentration of a reactant against time and a graph of the rate against the concentration of that reactant. In which option do the two graphs correspond to the same order of reaction? A. Pair A B. Pair B C. Pair C D. Pair D
A laboratory tests a urine sample for steroid drugs. Before the compounds in the extract are identified, they must be separated from one another. State a technique that can be used to separate the compounds.
A forensic laboratory identifies a solvent by mass spectrometry. The mass spectrum of a sample of pentan-3-one, CH3CH2COCH2CH3, Mr 86, is shown. Explain how the peaks at m/z 86 and m/z 57 support the identification of the compound as…
A detector tube for propan-2-ol vapour in workplace air contains orange dichromate ions, which turn green as they are reduced to chromium(III) ions. Cr2O72−(aq) + 14 H+(aq) + 6 e− → 2 Cr3+(aq) + 7 H2O(l) Deduce the half-equation for the oxidation of…
The temperature of a reaction mixture is raised and the rate constant, k, increases. Which statement best explains why? A. The activation energy of the reaction decreases B. The reaction becomes more exothermic C. More particles are present in the same…
At a certain temperature the equilibrium constant for the reaction H2(g) + I2(g) ⇌ 2 HI(g) is Kc = 64. Which value is the equilibrium constant of the reaction below at that temperature? A. 32 B. 8.0 C. 0.125 D.…