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While Writing a Mock exam, I stumbled upon a molar mass calculation which i couldn't answer
"Each tablet contains the same number of moles of CaCO and MgCO. One tablet reacted with excess hydrochloric acid to produce 0.24dm^3 of carbon dioxide at r.t.p
(i) Calculate how many moles of CaCO there are in one tablet
Number of moles CO2 =
Number of moles of CaCO3 and MgCO3 =
Number of moles of CaCO3 =
Any help would be much appreciated.
You just add up the mass number for each of the compounds and put the unit grams on the end. So for CO2 there would by 12+(16x2) = 44g
(Basically you just work out the Mr - relative formula mass - and it's in grams.)
I think that's right - hope it helps!
moles are easy when you understand them but sadly i didnt
Number of moles CO2 =0.24/24=0.01 mol.
Number of moles of CaCO3 and MgCO3 = mole ratio CaCO3:CO2 is 1:1 =2(0.01)=0.02 mol
Number of moles of CaCO3 = 0.02/2=0.01 mol.
Hope this helps.