# Can someone please explain how to work this out

Compounds A and B react together to form an equilibrium mixture containing
compounds C and D according to the equation
2A + B 3C + D
(a) A beaker contained 40 cm3 of a 0.16 mol dm–3 aqueous solution of A.
9.5 × 10–3 mol of B and 2.8 × 10–2 mol of C were added to the beaker and
the mixture was left to reach equilibrium.
The equilibrium mixture formed contained 3.9 × 10–3 mol of A.
Calculate the amounts, in moles, of B, C and D in the equilibrium mixture
Amount of B ____________________ mol
Amount of C ____________________ mol
Amount of D ____________________ mol
(5)
Original post by metricmetric
Compounds A and B react together to form an equilibrium mixture containing
compounds C and D according to the equation
2A + B 3C + D
(a) A beaker contained 40 cm3 of a 0.16 mol dm–3 aqueous solution of A.
9.5 × 10–3 mol of B and 2.8 × 10–2 mol of C were added to the beaker and
the mixture was left to reach equilibrium.
The equilibrium mixture formed contained 3.9 × 10–3 mol of A.
Calculate the amounts, in moles, of B, C and D in the equilibrium mixture
Amount of B ____________________ mol
Amount of C ____________________ mol
Amount of D ____________________ mol
(5)

Calculate the moles of A you had initially using the volume and concentration.

Now use change in moles of A = initial moles of A - moles of A at equilibrium

Now you use the ratios in the equation to work out how many moles of B react and how many moles of C and D are produced from the change of moles of A.

To find the moles of B and C present:

Moles of B at equilibrium = moles of B added - moles of B that react

Moles of C at equilibrium = moles of C produced + moles of C added
(edited 9 months ago)