DAT Destroyer GC #273

[Ashish]

Hey guys can anyone explain why it is okay to assume 1 mol of H2O is being used in this problem?

Since,
Mol fraction of gas dissolved in water (2x10^-18) = (mol of gas)/ (mol of gas+mol of water), how can we simply assume 1 mol of water?

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[DAT Destroyer]

Hey guys can anyone explain why it is okay to assume 1 mol of H2O is being used in this problem?

Since,
Mol fraction of gas dissolved in water (2x10^-18) = (mol of gas)/ (mol of gas+mol of water), how can we simply assume 1 mol of water?

Usually you assume one mole of solvent, unless otherwise stated.
If you are given a mole fraction only, you can assume one mole of solvent, because any moles you plug in will give you the same answer.

Hope this helps.

 

[Ashish]

Ah! seems so simple now. I took that long and the complicated route by making algebraic equations...

 

[DAT Destroyer]

Ah! seems so simple now. I took that long and the complicated route by making algebraic equations...

 

[SE111894]

Why are we able to assume that the mole fraction 2x10^-18 is equal to the number of moles in solution? Is it because the solution only consists of the gas and water?