Chemistry: Henry's law of partial pressure of gas.

[Mr Virtual]

Homework Statement

This is not a textbook question.
Henry's Law states that:
p=kx
where p=pressure of gas
x=mole fraction of gas in solution
k= Henry's constant

and k=p/x
So, we can say that k tells us the pressure of gas per unit x.
Which means k tells us the pressure of the gas when its mole fraction, x is unity.
But what does x=1 mean, since
x=no. of moles of solute/(no. of moles of solute + no. of moles of solvent)

if x=1
then this means: moles(solute)>>moles(solvent)
Am I wrong?

The value of k for helium dissolved in water is 144.97
What does it mean?

Please explain...


Mr V

 

[chaoseverlasting]

When x=1, it means that only that substance is present. I.e., its a pure substance. Hence, when only that gas is present, k is its pressure at that temperature/volume/per mole.