Answer:
The concentration is 12M
Explanation:
In this question, we are asked to calculate the concentration of the alkali given the information in the question.
To answer this question correctly, the first thing to do is to write the complete chemical equation of the reaction of the acid and the alkali. We identify that LiOH is the alkali and HCl is the acid
LiOH + HCl ———-> LiCl + H2O
we can deduce that 1 mole of the acid used up a mole of the base.
Now, we use the titration formula;
CaVa/Na. = CbVb/Nb
since Na= Nb = 1 i.e number of moles , we can just write the formula to be
CaVa. = CbVb
Where Ca is the concentration of the acid which is 4M
Va is the volume of acid used which is 60mL
Cb is the concentration of the base which is ?
Vb is volume of base which is 20mL
Plugging these values, we have;
4 * 60 = Cb * 20
Cb = 240/20
Cb = 12M
The concentration of the base is thus 12M