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Transcription of this question: 5.Carbonated water is produced when carbon dioxide is dissolved in water under pressure.The following equilibria are established.Equilibrium (1)Equilibrium (2)H20 (l)) C02C02 (aq) + H20 (l) H* (aq) + HC03- (aq)(a) Carbon dioxide acts as a weak acid.(i) Distinguish between a weak and strong acid.Weak acid:Strong acid:(ii)The hydrogencarbonate ion, produced in Equilibrium (2), can also act as an acid.State the formula of its conjugate base.(b) When a bottle of carbonated water is opened, these equilibria are disturbed.State, giving a reason, how a decrease in pressure affects the position of Equilibrium (1).(c)(d)At 298K the concentration of aqueous carbon dioxide in carbonated water is0.200moldm-3 and the PK. for Equilibrium (2) is 6.36.Calculate the pH of carbonated water.Soda water has sodium hydrogencarbonate, NaHC03, dissolved in the carbonated water.(i) Identify the type of bonding in sodium hydrogencarbonate.Between sodium and hydrogencarbonate:Between hydrogen and oxygen in hydrogencarbonate:(ii)Predict, referring to Equilibrium (2), how the added sodium hydrogencarbonateaffects the PH. (Assume pressure and temperature remain constant.)[2][2](iii)(iv)100.0cm3 of soda water contains 3.0 x 10-2g NaHC03.Calculate the concentration of NaHC03 in mol dm-3The uncertainty of the 100.0cm3 volumetric flask used to make the solution was±O.6cm3.Calculate the maximum percentage uncertainty in the mass of NaHC03 so thatthe concentration of the solution is correct to ±1.0[2]The reaction of the hydroxide ion with carbon dioxide and with the hydrogencarbonateion can be represented by Equations 3 and 4.Equation (3) OH-(aq) + C02(g) HC03- (aq)Equation (4) OW(aq) + HCOC(aq) H20(l) + C032-(aq)Discuss how these equations show the difference between a Lewis base and aBrønsted—Lowry base.Equation (3):Equation[2](f)Aqueous sodium hydrogencarbonate has a pH of approximately 7 at 298K.Sketch a graph of pH against volume when 25.0cm3 of 0.100 moldm-3 NaOH(aq) isgradually added to 10.0cm3 of 0.0500 mol dm-3 NaHC03 (aq).[2]14121010152025Volume of O. 100 mol dm-3 sodium hydroxide / cm3

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