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Bathers release nitrogen-containing compounds, including ammonia, into the pool water. Ammonia reacts with hypochlorous acid to form chloramines. (i) Deduce an equation for the reaction of ammonia with hypochlorous acid that forms trichloramine,…
Some users have asked for the water to be heated in winter. Suggest two reasons why leaving the water unheated is the better choice for the environment.
Determine the empirical formula of HA from the percentage composition.
A solution is prepared by dissolving 1.29 g of HA in water and making the volume up to 20.00 cm3. When the whole of this solution is titrated with 0.600 mol dm−3 sodium hydroxide, NaOH(aq), exactly 24.90 cm3 of the…
State the molecular formula of HA, using your answers to (a) and (b).
HA reacts with aqueous sodium carbonate according to the equation: 2 HA(aq) + Na2CO3(aq) → 2 NaA(aq) + CO2(g) + H2O(l) Identify the functional group in HA that is responsible for this reaction.
The IR spectrum of HA is shown. Two absorption bands are labelled: Y is a very broad band centred near 3000 cm−1 and Z is a band of medium intensity near 1650 cm−1. (i) Using section 20 of the data booklet, identify the functional…
Heavy water, , boils at 101.4 °C, whereas ordinary water, , boils at 100.0 °C at the same pressure. Which statement is correct? A. The boiling points differ because molecules have a greater mass, while the chemical…
Identify two controlled variables in this investigation.
The student measures the hydrogensulfite concentration by titrating samples against a standard iodine solution, with starch as the indicator. Every three days, 25.00 cm3 of cordial is withdrawn from each flask, diluted to 250.0 cm3 with…