Question (1 Viewer)

[Althea]

Hey there,

Could anyone please help me with this assignment question?

Sodium carbonate is mixed with an excess of hydrochloric acid. The reaction mixture lost mass, due to 700 mL of carbon dioxide gas escaping.

If the mixture was evaporated to obtain sodium chloride crystals, what mass of NaCl (s) whould be obtained? The molar volumes of gases at 100.0kPa and 25*C is 24.784 L.

Ahh - just can't get it! Too much of this for one day... thanks in advance for any help.


Blanker - Althea.

 

[cko]

Na2CO3 + 2HCl(excess) CO2 + H2O + 2NaCl

n(CO2) = V/Vm
= 0.7/24.784
CO2 = 0.028 mol (to 2 d.p.)

n(CO2) : n(NaCl)
1 : 2
0.028 : x
Hence x = 0.056
Therefore n(NaCl) = 0.056 mol

n=m/M
Hence m=nM
m(NaCl)= 0.056 *58.44
= 3.273g

therefore the mass of NaCl is 3.273g

Well this is my answer, I tried but if it's wrong don't be surprised. Calculations aren't my strong point.

 

[scotty schaefer]

No you are totally correct. This topic is somewhere else too and that is the answer all 3 of us who attempted it got, including CM-Tutor.

 

[Althea]

Yah - sorry! I posted it in the Acidic Environment too

Thanks for everyones help!