Question

-5.95g of cobalt(II) carbonate were added to 40cm3 of hydrochloric acid, concentration 2.0mol/dm3
.
I] Calculate the maximum yield of cobalt(II) chloride-6-water and show that the cobalt(II) carbonate was in excess.

CoCO3 + 2HCl → CoCl2 + CO2 + H2O
CoCl2 + 6H2O → CoCl2.6H2O

} maximum yield:
} number of moles of HCl used =
} number of moles of CoCl2 formed =
} number of moles of CoCl2.6H2O formed =

} mass of one mole of CoCl2.6H2O = 238g
}maximum yield of CoCl2.6H2O = …………………………………………………..…..…g
to show that cobalt(II) carbonate is in excess:
number of moles of HCl used = ……………………….……… (use your value from above)

mass of one mole of CoCO3 = 119g

number of moles of CoCO3 in 5.95g of cobalt(II) carbonate = …………………………

(ii) Explain how these calculations show that cobalt(II) carbonate is in excess.