40 ml of 0.05 M solution of sodium sesquicarbonate (Na2
CO3
.NaHCO3
.2H2
O)
is titrated against 0.05 M HCl. x ml. of HCl is used when phenolphthalein is
indicator and y ml. of HCl is used when methyl orange is the indicator in two
separate titrations. Hence (y – x) is

Question

40 ml of 0.05 M solution of sodium sesquicarbonate (Na2
CO3
.NaHCO3
.2H2
O) 
is titrated against 0.05 M HCl. x ml. of HCl is used when phenolphthalein is 
indicator and y ml. of HCl is used when methyl orange is the indicator in two 
separate titrations. Hence (y – x) is

aaronq · Answer

so you have 40 mL of 0.05M NaHCO3

using molarity=moles/V,  you find that there is 0.002 moles

are you trying to find how many mL of HCl you used?

aaronq · Answer

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