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(i) Sulfur dioxide is oxidized to sulfur trioxide by nitrogen dioxide in the atmosphere. Determine the enthalpy change, ΔH⊖, in kJ mol−1, for the reaction SO2(g) + NO2(g) → SO3(g) + NO(g) given these reactions and enthalpy…
The oxidation of sulfur dioxide to sulfur trioxide is an equilibrium reaction. 2 SO2(g) + O2(g) ⇌ 2 SO3(g) (i) State the equilibrium constant expression, K, for the reaction. (ii) Explain, with a reason, how compressing the gas mixture at constant…
What is the correct electron configuration of the selenium atom? A. 1s22s22p63s23p63d104s24p4 B. 1s22s22p62d103s23p64s24p4 C. 1s22s22p63s23p63d104s24p6 D. 1s22s22p63s23p63d84s24p6
(i) Determine the enthalpy of combustion of pentane, in kJ mol−1, using table 12 in the data booklet. C5H12(g) + 8 O2(g) → 5 CO2(g) + 6 H2O(g) (ii) Calculate the mass, in g, of carbon dioxide, CO2, produced when 45.0 g of pentane react with…
Pentane reacts with bromine, Br2, to form 2-bromopentane. (i) Explain, using equations, the initiation step and two propagation steps for this reaction. (ii) State one termination step for this reaction.
Pentan-2-ol can form by reacting pent-1-ene with water in the presence of an acid catalyst. CH2=CHCH2CH2CH3(g) + H2O(l) → CH3CH(OH)CH2CH2CH3(aq) ΔH⊖ = −84 kJ mol−1 (i) Explain why increasing the temperature would increase…
Pentan-2-ol will react with acidified potassium dichromate, K2Cr2O7, which is an oxidizing agent. State the name of the product of this reaction.
Which species has the ground state electron configuration [Ar] 3d8? A. Cu2+ B. Zn2+ C. Ni D. Ni2+
(i) Describe the structure of solid magnesium and state the forces that hold it together. (ii) Explain why a piece of magnesium can be hammered into a new shape without breaking. (iii) Explain why the melting point of magnesium is higher than that of sodium.
An alloy of magnesium and aluminium is used for car wheels and laptop casings. (i) Suggest why adding aluminium produces a material that is harder and less malleable than magnesium alone. (ii) Suggest why a magnesium alloy is a good choice for the casing of a…