Question

When the relative humidity is 90%, we say the air is: supercooled superheated saturated humid

Answer 1

Step-by-step explanation:

The amount of moisture present in air at a given temperature is known as humidity.

Whereas relative humidity is the amount of percentage of moisture it contains when compared to the maximum moisture it can contain at a given temperature.

Also % Relative humidity (RH) =
`(P)/(P_(vap))`

where, P = the partial pressure of water vapour

`P_(vap)` = the equilibrium vapor pressure at a particular temperature.

Accrding to the Clausius-Clapeyron equation,
`P_(vap)` decreases with decrease in temperature.

Hence, it means that at super-cooled conditions the %RH would be 100%.

On the other hand, the temperature will be very high at super-heated conditions.

Hence,
`P_(vap)` will be high hence %RH will be low.

It is also known that at saturated condition, P =
`P_(vap)`

Therefore, %RH is 100.

Thus, we can conclude that when the relative humidity is 90%, we say the air is humid.