Question

In each pair of compounds, pick the one with the higher vapor pressure at a given temperature. Explain your reasoning.

a. CH4 or CH3CI
b. CH3CH2CH2OH or CH3OH
c. CH3OH or H2CO

Answer 1

The answer is:

`PART \ A: CH_4\\\\PART \ B: CH_30H\\\\PART \ C: H_2CO`

Step-by-step explanation:

Parts A:

The vapor pressure is higher in
`CH_4` because it is non-polar, while
`CH_3Cl` is polar.
`CH_4` has a lower molar weight as well.

Part B:

Although hydrogen bonding is found in both commodities, the vapor pressure is higher because of the smaller molar mass of
`CH_30H`.

Part C:

`H_2CO` does not show hydrogen due to the increased vapor pressure

`CH_3OH` bonding.