# Chemistry

posted by .

I titrated 0.25g of soda ash mixed with 25mL of deionized water and it took 43.7mL of hydrochloric acid to complete the titration.
I am trying to figure out how to find the moles of sodium carbonate in the soda ash and then the percent of sodium carbonate in the soda ash. How would I go about doing this calculation?

• Chemistry -

It's important to know what you used as an indicator. If you used phenolphthalein you titrated to the HCO3^- end point. If you used methyl orange or methyl red you titrated to the H2CO3 (H2O + CO2) end point. I will assume that's the one you used.(I think M.R. is better than M.O. but I believe you want to change about pH of 5)
In addition you don't give the molarity of the HCl.

mols HCl = M x L = ?
mols Na2CO3 = 1/2 mols HCl(from the equation of
Na2CO3 + 2HCl ==> 2NaCl + H2O + CO2
g Na2CO3 = mols Na2CO3 x molar mass Na2CO3.
Then %Na2CO3 = (g Na2CO3/0.25g)*100 = ?

• Chemistry -

I used bromophenol blue as the indicator, and the molarity of HCl is 0.2M.

• Chemistry -

You titrated to the CO3^2- end point so the equation chemistry is what I indicated. I've never used that indicator. I always used methyl red and titrated until the indicator turned, heated to drive off CO2 (the m.r. turned back basic, and I titrated to the end point (much sharper end point the second time around). Since bromophenolblue turns at a more acid end point, you may not be required to heat the solution to drive off CO2.

• Chemistry -

I have done the calculation for this multiple times and I keep getting over 100% for the sodium carbonate in soda ash. I have no idea what I am doing wrong. I did it the way that you explained.

## Similar Questions

1. ### Chemistry

Washing soda is added to hard water to allow soap to lather. A certain brand of washing soda contains partially hydrated sodium carbonate solid. A 0.300 g sample completely reacts with 20.0 mL of 0.250 M hydrochloric acid. a What mass …
2. ### Chemistry

This is for a titration, to measure the amount of acid that can be neutralised by gaviscon. I know how to work out the first 3 but I'm not sure on the others. I think i need to use the calculation c=n x v but i don't know where and …
3. ### Chemistry

Find the Molecular weight of unknown acid #5... Mass of acid #5 = 1.200g Volume (acid was mixed in) = 100ml (distilled water) Conectration of NaOH = 0.989 M Aliquot of acid titrated with NaOH = 25ml = 0.025 L Average volume of NaOH …
4. ### Chemistry

How can i explain the key features of the periodic table relate to the conclusions after a titration experiment The experiment was the preperation of a standard solution of sodium carbonate and titration for the equation between hydrchloric …
5. ### chem

If 0.752 g of pure sodium carbonate was dissolved in water and the solution titrated with 25.90 mL of hydrochloric acid to a methyl orange end point, calculate the molarity of the hydrochloric acid solution. (Hint: This process takes …
6. ### chemistry

In a standardization titration involving hydrochloric acid and sodium carbonate, a student recoirded the following results for the volume of hydrochloric acid used against 10.00mL of the sodium carbonate solution : 15.60; 14.50; 14.70 …
7. ### Chemistry

FB1 is a solution containing a mixture of potassium carbonate and sodium hydrogen carbonate . 25cm^3 of this mixture was to titrated against 0.250mol/dm^3 solution of HCL. In one titration using phenolphthalein as indicator, 10.00cm^3 …
8. ### chem

A sewage cleanser contains concentrated hydrochloric acid (HCl) as the active ingredient. A titration experiment was carried out to determine the concentration of hydrochloric acid in the domestic cleanser. 25.0 mL of the cleanser …
9. ### chemistry

Explain why sodium carbonate against hydrochloric acid titration using phenophthalein titration do not go to completion but stop at the sodium hydrogen carbonate stage.
10. ### Chemistry

a domestic cleaner contains concentrated hydrochloric acid as the active ingredient. a titration experiment was carried out to determine the concentration of hydrochloric acid in the domestic cleanser. 20.0mL of the cleanser were diluted …

More Similar Questions