Initially there were 1.0mol of a and 0.2 mol of b in the reaction mixture.a and b reacted together to produce an equilibrium mixture containing 0.04mol of c.the total volume of the mixture was 2.00dm^3.

A.Calculate the number of moles of (a) and (b) at equilibrium.

OK. So you posted the problem incorrectly. Of course the answers don't agree. Just do the problem as I've shown with the correct values.

To calculate the number of moles of substances (a) and (b) at equilibrium, we need to establish the stoichiometry of the reaction and use the information given.

From the information provided, we know that initially, there were 1.0 mol of substance (a) and 0.2 mol of substance (b). We are also informed that substance (a) and substance (b) reacted together to produce an equilibrium mixture containing 0.04 mol of substance (c).

Since we are not given the balanced chemical equation for the reaction, let's assume a general equation:

aA + bB ⇌ cC

Now, we need to determine the change in the number of moles for each substance in the reaction. At equilibrium, the number of moles of (c) is 0.04 mol.

To calculate the number of moles of (a) and (b) at equilibrium, we need to consider the stoichiometry of the reaction. If the equation is balanced, it will give us the mole ratio between the reactants and products.

Let's assume that a mole of (a) reacts with b moles of (b) to produce c moles of (c).

Given that the equilibrium mixture has 0.04 mol of (c), we can use the stoichiometry to calculate the number of moles of (a) and (b) at equilibrium.

Assuming that the molar ratio of (a) to (b) is 1: b, we can set up the following equation using the given information:

1 + b = c

Substituting the known values:
1 + b = 0.04

Now, solve for b:
b = 0.04 - 1
b = -0.96

Since the calculated value for b is negative, it indicates that the assumption for the stoichiometry or the given information may not be accurate. Please double-check the information and ensure that it aligns with the stoichiometry of the reaction to correctly determine the number of moles of (a) and (b) at equilibrium.

The answer for this question is o.o8 and 0.18 and a is 0.1 in question not 1.0

..................A + B ==> C

I................1.0...0.2......0
C..............-x.......-x.......+x
E.............1.0-x....0.2-x....x

x = 0.04.Calculate the others from the E line.