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bluedicius
Dec 4, 2004, 05:41 PM
I've been asked this question:
What volume of carbon dioxide gas at 100kPa and 35C is produced by the complete reaction of 50mL of a 0.200 mol/L baking soda solution with excess hydrochloric acid?

And this is what I've started with for solving it.

NaHCO3 + HCl --> NaCl + CO2 + H2O

CO2
v
100kPa, 35C (35 + 273K)

I don't know if I'm right but with what I have so far but, what I'm wondering is
What do they mean by 'is produced by the complete reaction of 50mL of a 0.200 mol/L baking soda solution with excess hydrochloric acid?' Are the meaning 50ml and 0.200mol/L of just baking soda or of just hydrochloric acid or of both?
Thanks

Amb_Tovan
Sep 24, 2005, 03:14 PM
well, since n = cv

and your balanced equations indicates that everything is a one to one mole ration I believe it is the same difference using 0.200 mol/l as both concentration and 50 ml as volume. Since the mole ratio is one to one, both will have the same amount of moles eh?

The number of moles should be 0.01, you take this number and substitue into pv=nRT and the volume of CO2 is easy to find.

kp2171
Oct 8, 2005, 10:13 PM
> what do they mean by 'is produced by the complete reaction of 50mL
> of a 0.200 mol/L baking soda solution with excess hydrochloric acid?'
> Are the meaning 50ml and 0.200mol/L of just baking soda or of just
> hydrochloric acid or of both?

Means that baking soda and HCl are mixed, but there is more than enough HCl to completely convert all the baking soda... therefore the baking soda is the limiting reagent in this question...

They could've given you amounts and concentrations for the HCl as well and made you figure out which chemical is in excess... but this way is easier for you. You just use the baking soda numbers to get moles and solve. You convert temp and pressue to appropritate Si units, and with the # moles from the baking soda you can solve for V.