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Which pair of compounds correctly illustrates the stated type of isomerism? A. Positional isomerism: CH3CH2CHO and CH3COCH3 B. Functional group isomerism: CH3CH2CH2CH2OH and CH3CH(OH)CH2CH3 C. Cis-trans isomerism: the two compounds…
When the equation for the complete combustion of 1 mol of pentan-1-ol, C5H11OH, is balanced, what is the sum of all the coefficients? Unbalanced equation: C5H11OH(l) + O2(g) → CO2(g) + H2O(l) A. 19 B. 19.5 C. 20 D. 39
The potential energy profile of a reaction is shown. Which reaction has this energy profile? A. Cl2(g) → 2 Cl(g) B. CaCO3(s) → CaO(s) + CO2(g) C. N2O4(g) → 2 NO2(g) D. 2 Mg(s) + O2(g) → 2 MgO(s)
The standard enthalpy changes of two reactions are given below. N2(g) + O2(g) → 2 NO(g) ΔH⊖ = x kJ mol−1 2 NO(g) + O2(g) → 2 NO2(g) ΔH⊖ = y kJ mol−1 What is ΔH⊖, in…
What is the enthalpy change, in kJ mol−1, for the formation of methanol from carbon monoxide and hydrogen? CO(g) + 2 H2(g) → CH3OH(l) A. −726 + 2(−286) − 283 B. −283 + 2(−286) + 726 C. −283 − 2(−286) + 726 D. −726 − 2(−286) − 283
Which statement describes a disadvantage of using bioethanol rather than petrol (gasoline) as a fuel for cars? A. The carbon dioxide released when bioethanol burns was recently removed from the atmosphere by the crop B. Bioethanol releases less energy per…
Which equation represents the enthalpy change of atomization, ΔHat, of iodine? A. I2(s) → I2(g) B. I2(g) → 2 I(g) C. D.
Which set of products can be formed by the incomplete combustion of butane, C4H10? A. C, CO and H2O B. CO2 and H2O only C. CO and H2 only D. C and H2 only
Which statement best describes an environmental consequence of using fossil fuels? A. The carbon dioxide released is completely absorbed by the oceans, so its concentration in the atmosphere does not change. B. Coal has a higher hydrogen to carbon ratio than…
A sealed glass tube contains solid iodine in equilibrium with iodine vapour at constant temperature. Which of the following could be observed? A. The purple colour of the vapour gradually becomes more intense B. The total mass of the solid decreases steadily…