Bio 189 Water, Aqueous Solutions, and Concentration

Why is water considered a polar molecule?

) Oxygen is more electronegative than hydrogen, creating partial charges

Which of the following best describes hydrogen bonding in water?

Weak attractions between the δ+ hydrogen of one water molecule and the δ– oxygen of another

What property of water allows it to stick to itself?

Cohesion

Which of the following is an emergent property of water?

c) It expands upon freezing

Why is water’s high specific heat capacity important to life?

It prevents organisms from overheating too quickly

Which of the following best describes adhesion?

Water molecules sticking to other substances

What is transpiration in plants?

The loss of water vapor through the leaves

Which process contributes most to evaporative cooling?

High-energy water molecules escaping as vapor

How does adding ice to a beverage lower its temperature?

Ice absorbs heat as it melts, lowering the temperature

Why does ice float on water?

Ice is less dense due to the hydrogen bonds forming a structured lattice

What happens to the density of water when it is heated?

It decreases

A solution is composed of:

A solute dissolved in a solvent

What is the molarity of a solution with 1 mole of solute dissolved in 1 liter of solution?

1 M

What happens to the rate of evaporative cooling in high humidity?

It decreases

Which of the following is the correct order of concentration terms from highest to lowest?

% > ‰ > ppm > ppb > ppt