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Which statements are correct for the complex ion [CoCl4]2−? I. The oxidation state of cobalt is +4. II. The chloride ions act as Lewis bases. III. The coordination number of cobalt is 4. A. I and II only B. I and III only C. II and III only D. I, II…
What is the oxidation state of chromium in the complex [Cr(NH3)4Cl2]Cl? A. +1 B. +2 C. +3 D. +7
Which statement is correct about an SN1 mechanism? A. The rate of reaction depends on the concentrations of both the halogenoalkane and the nucleophile. B. The rate-determining step forms a carbocation intermediate from a single molecule. C. The…
Which compound is the major product when 2-methylpropene, (CH3)2C=CH2, reacts with hydrogen chloride, HCl? A. (CH3)3CCl B. (CH3)2CHCH2Cl C. CH3CHClCH2CH3 D. (CH3)2CClCH2Cl
Two pigments extracted from a leaf are separated by thin-layer chromatography on a silica plate (a polar stationary phase) using a non-polar solvent as the mobile phase. Pigment X travels further up the plate than pigment Y. Which statement explains the…
Deduce the oxidation state of chlorine in each of the three chlorine-containing species in the equation. Cl2: HOCl: Cl−:
The pool operators add sodium carbonate to the water to raise its pH. Explain why a larger proportion of the dissolved chlorine reacts with water after the sodium carbonate has been added.
A student writing a report on chlorine as a disinfectant collects, from several websites and reference books, values for how much chlorine dissolves in pure water at various temperatures. (i) Identify one difficulty in comparing the solubility values from…
Most pools, including this lido, are dosed with sodium hypochlorite solution, NaOCl(aq), instead of chlorine gas. Suggest why pool operators avoid dosing the water with chlorine gas itself.
Hypochlorous acid is a weak acid. In water it is in equilibrium with its conjugate base, the hypochlorite ion, OCl−, which kills microorganisms far less effectively than the acid molecule does. The graph shows what percentage of the dissolved chlorine…