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# Acid-base titration calculations watch

1. Any help with question 2 would be hugely appreciated! Thank you.
2. (Original post by jamiescriven)

Any help with question 2 would be hugely appreciated! Thank you.
So your two reactants are HCl and NaHCO3.

(33.2X0.1)/1000= 3.32x10-3 mols of HCl.
The molar ratio is 1:1 so there are also 3.32x10-3 mols of NaHCO3
This is for 25cm3 however so multiply by 10 which gives 0.332 mols of NaHCO3 in 250cm3.
This needs to be converted into grams:
The Mr for NaHCO3 is 84.
84X0.332= 2.7888g of NaHCO3 in the tablet.
(2.7888/mass of tablet in total)X100= 58.6% which is the % by mass of NaHCO3 in the tablet.
3. (Original post by JimJam456)
So your two reactants are HCl and NaHCO3.

(33.2X0.1)/1000= 3.32x10-3 mols of HCl.
The molar ratio is 1:1 so there are also 3.32x10-3 mols of NaHCO3
This is for 25cm3 however so multiply by 10 which gives 0.332 mols of NaHCO3 in 250cm3.
This needs to be converted into grams:
The Mr for NaHCO3 is 84.
84X0.332= 2.7888g of NaHCO3 in the tablet.
(2.7888/mass of tablet in total)X100= 58.6% which is the % by mass of NaHCO3 in the tablet.
NaHCO3 is sodium bicarbonate right? But in the question it says the second reactant is hydrated sodium carbonate, so wouldn't that be NaCO3.xH2O?
4. (Original post by jamiescriven)
NaHCO3 is sodium bicarbonate right? But in the question it says the second reactant is hydrated sodium carbonate, so wouldn't that be NaCO3.xH2O?
Sodium Hydrogen Carbonate. Considering the information available that's the only thing I thought it could be.
5. (Original post by jamiescriven)
NaHCO3 is sodium bicarbonate right? But in the question it says the second reactant is hydrated sodium carbonate, so wouldn't that be NaCO3.xH2O?
It would but you're only interested in finding the mass of NaHCO3 and then comparing it to the actual mass of the tablet, so the actual structure of the hydrated bicarbonate is irrelevant.

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