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Transcription of this question: 4.A molecule of citric acid, C6HE07, is shown.HOThe equation for the first dissociation of citric acid in water is(a)0)(ii)C6HE07 (aq) + H20(l) CEH70A(aq) +Identify a conjugate acid—base pair in the equation.The value of K. at 298K for the first dissociation is 5.01 x 10-4State, giving a reason, the strength of citric acid.(iii)(iv)The dissociation of citric acid is an endothermic process. State the effect on thehydrogen ion concentration, [He], and on KS, of increasing the temperature.Effect on [W]Effect on K,Calculate the standard Gibbs free energy change, AGO, in kJ mol-l, for the firstdissociation of citric acid at 298K, using section 1 of the data booklet.(v)Comment on the spontaneity of the reaction at 298K.(b) Outline two laboratory methods of distinguishing between solutions of citric acid andhydrochloric acid of equal concentration, stating the expected observations.