A 0.720g sample contains only NaHCO3 and
Na2CO3, 0.360g of the sample used 50.00 mL of
0.100M HCl solution to reach the end point in the reaction. How
many millimoles of HCl reacted with the sample? If there is x
millimole of Na2CO3 and y millimole of
NaHCO3 in 0.360g of sample, complete the blank in the
following equation.
___x +___y = _________ mmole HCl
For the same sample from above, the other 0.360g of the sample
was added firstly with 50ml 0.100 M KOH and secondly with excess
amount of BaCl2. Then the sample was titrated with 20ml
of 0.100M HCl to reach the end point of the reaction.
What is the chemical reaction after adding excess amount NaOH
to the sample?
What is the chemical reaction after adding excess amount of
BaCl2 to the sample?
Before reaching the end point (BaCO3 still exists as
precipitate), what is the chemical reaction when the sample was
titrated with HCl?
The sample was back-titrated with 20ml of 0.100M HCl to reach
the end point of the reaction. How many millimoles of KOH was in
excess? How many millimoles of KOH has reacted with
HCO3-?
How many the millimole of CO3 2- in the
0.360g of sample? What is the mass percent of
Na2CO3 in this sample?