i apologize if you find it insulting . im sorry
hahaha, im just messing around , alrigth then ill try my best to explain each part
number of moles of NiCO3 = 0.08 mols
cuz its says that the number of moles of sulphuric acid in 40cm3 of 2.0 mol/dm3 = 0.08 mol
and the reaction goes like this
NiCO3 + H2SO4 ----> NiSO4 + CO2 + H2O
only 1 mol of NiCO3 reacted not 2 or 3 cuz if it was it would be :
2NiCO3 or anything else
and also 1 mol of H2SO4 reacted
so if 1 mol of H2SO4 is 0.08 (like it mentions) that means also 0.08 mol of nickel carbonate reacted
because it is 1:1 ratio
did u get the first part?