URGENT chemistry help

A student bubbled 240cm3 of CO2 into 400cm3 of 0.10mol-1 lithium hydroxide solution.

the equation for the reaction is
2LiOH (aq) + CO2 (g) ---> Li2CO3 (aq) + H2O (l)

calculate the number of moles of lithium hydroxide that would not have reacted.

(take the molar volume of carbon dioxide to be 24 litres mol-1)

show working clearly

b) what is the pH of the 0.10mol-1 lithium hydroxide solution used in the experiment?

c) explain why lithium carbonate solution has a pH greater than 7.
In your answer you should mention the two equilibrium involved

I HAVE NO CLUE HOW TO DO THIS PLEASE HELP ME