Question

How many liters of 1.5 M HCl solution would react completely with 6.5 moles Ca(OH)2?

Answer 1

Moles of $Ca(OH) _{2}$ = 6.5 mol
mole ratio of $Ca(OH) _{2}$ : HCl =  1 : 2
     ∴ since $Ca(OH) _{2}$ cntain 6.5 mol, then HCL contains (2 * 6.5) mol
       Thus moles of HCl = 13.0 mol
   Volume of HCl needed = $\frac{moles}{molar concentration}$
                                        = $\frac{13.0 mol}{1.5 mol / dm^{3} }$ 
                                        =  8.67 $dm^{3}$
$since dm^{3} = L$
then volume of HCL needed = 8.67 L