At 40 degreee celcius the vapour pressure, in torr, of methyl aclohol-ethyl alcohol solutions is represented by P= 119x + 135 where x is the mole fraction of methyl alcohol. what are vapours pressures of the pure components at this tempreature?

Let, vapour pressure of methyl alcohol is pm ethyl alcohol has p​e . Similarly, the mole fractions are xm and xe then we have,
final pressure of solution :
P=pm0xm +pe0xe =pm0xm + pe0(1-xm)Or, P=(pm0-pe0) xm + pe0
Now, we have, the pressure of methyl alcohol is , =119x+135, then equating the value in avbove equation we get:
 P=(pm0-pe0) xm + pe0Or, P =119x+ 135So, that, pe0 = 135 torr(pm0-pe0) = 119So, pm0 = 119 +135 = 245 torr
Hence, the pure vapour pressure of ethyl alcohol is 135torr and pure methyl alcohol is 245 torr.

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