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Calculating Volumes of gas (1 Viewer)

fwuxed

Channeling Ki
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Sodium hydroxide reacts with carbon dioxide to form sodium carbonate and water. What volume of carbon dioxide (measured at 0C and 1.00 atmosphere pressure) will 100mL of1.35 mol/L solution of sodium hydroxide absorb?

2NaOH + CO2 ==> Na2CO3 + H2O

number of moles of Na2CO3 provided / number of moles of CO2 needed = 1/1 = 1

since it's at 0C and 1.00 atmosphere pressure, mols of Na2CO3 = 0.1L x 22.4 = 4.464 x 10^-3 mols

number of mols of CO2 needed: 4.464 x 10^-3
molar mass of CO2 = 12.01 + 16.00 x 2 = 44.01
since n = m / M, m = nM, therefore m = 4.464 x 10^-3 x 44.01 = 0.1964...

since CO2 is a gas at 0C and 1.00 atmosphere pressure,
volume of CO2 = 0.1964... x 22.4 = 4.401L

------------------------------------------------

See anything wrong with my working? Conquering chem says 1.51 L :mad:
 

Heinz

The Musical Fruit
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Firstly, you dont need to work out the molar mass of anything. From your equation, you can see that NaOH reacts with CO<sub>2</sub> in a 2:1 ratio. 100mL of a 1.35mol/L solution of NaOH means that 0.135mols are used. From the ratio, this means that 0.0675 mols of CO<sub>2</sub> are used and when multiplied with 22.41 (the old value at 0 degrees as opposed to the 22.71 we now use) you get 1.512675L
 

fwuxed

Channeling Ki
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Ah, fair enough.

Was copying the examples right above the question.
Who knew they were totaly unrelated. :(

Just realised i read the question wrong too
lol x_X
 
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