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A student compiles data on the solubility of bromine in water at different temperatures from several websites and textbooks. (i) Identify one problem that arises when the values from these sources are compared with one another. (ii) Each solubility is then…
Suggest why hot-tub owners rarely add bromine itself to the water and instead use solid tablets that release HOBr.
In water, HOBr partly ionizes to give the hypobromite ion, OBr−; the ion is a much weaker sanitizer than the un-ionized acid. The graph shows how the percentages of the dissolved bromine present as HOBr(aq) and as OBr−(aq) vary with pH at 25 °C.…
Ammonia from sweat and skin-care products reacts with HOBr to form bromamines: NH2Br, NHBr2 and NBr3. (i) Deduce an equation for the reaction of ammonia with HOBr(aq) that produces dibromamine, NHBr2(aq). (ii) The graph shows how…
Hot tubs are usually kept at 38–40 °C. Suggest two reasons why running a hot tub at a lower temperature would be better for the environment.
Determine the empirical formula of HA.
A 20.00 cm3 sample of a solution containing 1.21 g of HA is titrated with 0.500 mol dm−3 sodium hydroxide solution, NaOH(aq). Exactly 27.40 cm3 of the NaOH(aq) is required to neutralize the acid completely. Determine…
State the molecular formula of HA.
HA is neutralized by potassium hydroxide solution according to the equation HA(aq) + KOH(aq) → KA(aq) + H2O(l) Identify a functional group present in HA.
At 25 °C the density of heavy water, , is 1.11 g cm−3, while the density of ordinary water, , is 1.00 g cm−3. Which statement explains this difference? A. Each nucleus contains one…