Give reasons why
a) Air is dense at sea level
b) Alcohol evaporates faster than water

Dear student,
a) It can be explained using Boyle's Law.

According to Boyle's law, pressure is inversely proportional to volume, and, as we know that as height increases, pressure decreases. At the sea level, the pressure is more than that at high altitude, so, obviously, volume of air will be less at the sea level.

Now,

In the formula for density, if we keep the mass constant, we find that Density varies inversely with Volume. And, as already I've already explained above, volume at the sea level is less than that at higher altitudes, so , consequently, density of air is more at the sea level.

b)As the boiling point of alcohol is lower than water therefore it is more volatile and hence will evaporate faster.  

Hope this information will clear your doubts about topic.

If you have any more doubts just ask here on the forum and our experts will try to help you out as soon as possible.

Regards