11/20 notes Flashcards
Why does water have a high surface tension?
water has hig surface tension b/c it forms many H bomds and it exhbits capillary action
How does surface tension aid in capillary action?
surface tension acts to hold the surface intact. Capillary action occurs when the adhesion to the wall is stronger than the cohesive forces between the liquid molecules
Explain the shape of meniscus of water in a glass container versus mercury in a glass container.
water meniscus is concave and mercury is convex. Water molecules are more attracted to container, forms concvae. Meercury molecules are more attracted to themselves so forms convex
Using intermolecular forces, explain why water and nonpolar substances such as oils do not mix.
water and oils do not mix b/c like dissolves like. Water is polar and oil is non polar ommiscible so it forms two bomds
What is evaporation and how is it different from boiling?
evaporation is H2O L -> H2O g at any temperature. Boiling only occurs at specific temp, the boilng point
Why does increasing the temperature increase evaporation and vice versa? (You should be able
to draw a graph to support your answer.)
evaporation occurs more at higher temperature because more moelcules are moving faster so iy is more liely for a molecule to have enough energy to break away from liquid to become gas
For a liquid in a closed container, what does it mean to reach dynamic equilibrium?
rate of evaporation = rate of condensation (neitehr has stopped)
Define vapor pressure in this context.
vapor pressure is pressure exerted by the gas in equilibrium w/ a solid or liquid in a closed container at a given temp
why does IMF impact vapor pressure
b/c the stronger these forces, the lower the rate of evaporation and the lower the vapor pressure
does polar-polar dissolve
yes
does non poalr - non polar dissolve
yes
does polar-non polar immiscible dissolve
forms two layers
