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Which statement correctly describes a type of electrochemical cell? A. A secondary cell operates as a voltaic cell when discharging and as an electrolytic cell when it is recharged B. A primary (voltaic) cell converts electrical energy into chemical energy C.…
Which half-equation represents the reduction of sulfuric acid to sulfur dioxide in acidic solution? A. H2SO4 + 2 H+ + 2 e− → SO2 + 2 H2O B. H2SO4 + 4 H+ + 4 e− → SO2 + 2 H2O C. H2SO4 + 2 H2O → SO2 + 6 H+ + 2 e− D.…
Which compound is formed when pentan-2-one, CH3COCH2CH2CH3, is reduced? A. CH3CH2CH2CH2CH2OH B. CH3CH2CH2CH2COOH C. CH3CH2CH2CH2CHO D. CH3CH(OH)CH2CH2CH3
Which radical is most likely to form when one covalent bond in bromochlorodifluoromethane, CBrClF2, is broken by ultraviolet light in the upper atmosphere? A. •CBrF2 B. •CClF2 C. •CBrClF D. •CBrClF2
Which species is formed when a chlorine molecule undergoes homolytic fission in the presence of ultraviolet radiation? A. A chlorine radical, Cl ⋅ B. A chloride ion, Cl− C. A chlorine cation, Cl+ D. An excited chlorine molecule, Cl2 ⋅
Pent-2-ene undergoes a range of addition reactions. Which reagent and product are correctly matched? A. Reagent H2, product pent-1-ene B. Reagent Br2, product 2,3-dibromopentane C. Reagent H2O, product pentan-1-ol D. Reagent HBr,…
Which species is the electrophile in the reaction below? CH3CH2Cl + CN− → CH3CH2CN + Cl− A. CN− B. Cl− C. CH3CH2Cl D. CH3CH2CN
Which technique is used to obtain pure water from a solution of sodium chloride in water? A. evaporation B. distillation C. filtration D. paper chromatography
Deduce the oxidation state of bromine in the reactant and in each of the two products. Reactant Br2: Product HOBr: Product HBr:
When sodium hydroxide solution is added to the water, a larger amount of bromine reacts. Explain this observation.