Question

A chemical engineer is studying the following reaction: HCN(0g)+NH (aq) +CN (aq)+NH (aq) At the temperature the engineer picks, the equilibrium constant K, for this reaction is 0.75 The engineer charges ("fills") four reaction vessels with hydrogen cyanide and ammonia, and lets the reaction begin. He then measures the composition of the mixture inside each vessel from time to time. His first set of measurements are shown in the table below Predict the changes in the compositions the engineer should expect next time he measures the compositions. reaction compound concentration expected change in concentration HCN 1.02 M NH, 1.18 M 2 0 10 M 0.28 M o increase of increase O increase O increase O increase increase O increase o increase O. decrease o decrease O. decrease o decrease O. decrease Odecrease o decrease o decrease O(no change) O(no change) O(no change) O(no change) O(no change) O(no change) O(no change) O(no change) 020 M 0.36 M 0.92 M 1.10 M 1.02 M 1.18 M of increase o increase O increase o increase Odecrease o decrease o decrease Ot decrease O(no change) O(no change) O(no change) O(no change) OTOM NH 025M

Answer 1

HEN(aq) + NH3 Cao CN- (aq) + Why (aq), K= [[N] [NHu? [HN] NHẸ - 075 Reaction vessee - A Q = [cN"] [Nity] = {0.10] [0-28] - [HCN] [Na] 5.02] [118] = 0.028 1- 2036 ñ 0.023 (0.75 * Q,<k. To teach equilibrium , preactants should be consumed & mose products should fersm. Because By this only, nemesactions as a{[eN] {NH]} will increase and denominator of a f[HCN] {NH 3]} will decrease. At some point of time aftes, Q will be equal to k. so HCN = v deeseases NH3 = v decreases CN = 7 increases Nhy z ł increases.

Reaction vessel - B Q. [ON] ENHU [HCN] [NIHz (0.92) (1-10) ] (0.20) (0.365 = (-012 0.072 ~ 14.06 >0.75 2,> K. To teach equilibrium, numerater os Q{[[N][NH ] } should decrease & denominated on Q{ [HEN] [NH372 should increase so that in future, Q2 will be equal to k. Hence more & more product will give yeacuteents which a backwasd reaction. HON = q increase NH3 = 9 increase (N = deesease NHU = V decrease. Reaction vessel-c same concentration given as reaction vessee-Al so HCN=& deesease NHz =d decrease CN = 7 increase NHI = 7 increase
The reaction will always move towards equilibrium, hence when he check for next time the concentration are changed as per the equilibrium path.