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3. A(g)+B(g)AB(g)K=4.0102 0.50mol of A and 0.60mol of B were placed in a 2.0 L container. Calculate the concentration of AB at equilibrium. 4. At 773C, a mixture of CO(g),H2 (g) and CH3OH was allowed to come to equilibrium. The following equilibrium concentrations were then measured: [CO]=0.105M,[H2]=0.250M,[CH3OH]=0.00261M. Calculate K for the reaction CO(g)+2H2(g)CH3OH (g)