Properties of Water Quiz
Questions: 16 · 10 minutes
1. Small drops of water merge into a larger rounded drop on waxed paper. Which property most directly explains the attraction among the water molecules?
Adhesion
Low specific heat
Cohesion
Ionic bonding
2. At 25°C, a sample of pure water has approximately what pH?
0
5
14
7
3. Why can ordinary ice float on liquid water?
Hydrogen bonds hold ice in an open crystal structure that is less dense than liquid water.
Ice molecules lose oxygen atoms during freezing, reducing their mass.
Water molecules become nonpolar when they freeze.
The covalent O–H bonds break and create trapped hydrogen gas.
4. Water in a narrow clean glass tube forms a concave meniscus, with the edges slightly higher than the center. What does this indicate?
Gravity is stronger at the center of the tube.
Adhesion between water and glass is stronger than the inward cohesive effect at the edge.
Water has no cohesive attraction in narrow containers.
The glass converts surface water into vapor.
5. During transpiration, water can remain in a continuous column as it moves through a plant’s narrow xylem. Which properties contribute most directly?
Low specific heat and expansion during freezing
Cohesion among water molecules and adhesion to xylem walls
Chemical breakdown of water into hydrogen and oxygen
Nonpolarity and weak intermolecular attraction
6. When table salt dissolves in water, what happens around its sodium and chloride ions?
Water molecules become nonpolar and stop interacting with one another.
The ions form covalent bonds that create new water molecules.
Water molecules orient their partial charges around the oppositely charged ions.
Hydrogen gas forms and pushes the ions apart.
7. In liquid water, a hydrogen bond most commonly forms between which parts of neighboring molecules?
A hydrogen atom and the covalent bond inside the same molecule only
Two partially positive hydrogen atoms
Two oxygen nuclei joined by shared electrons
A partially positive hydrogen and a partially negative oxygen
8. Why does the bent geometry of water matter for its overall polarity?
It makes each O–H bond nonpolar.
It gives every water molecule a full negative charge.
It prevents the O–H bond dipoles from canceling each other.
It allows oxygen to form an ionic bond with each hydrogen.
9. Which description best explains why a water molecule is polar?
The molecule is linear, so its two O–H bond charges reinforce each other.
Hydrogen atoms transfer both of their electrons completely to oxygen.
Oxygen and hydrogen share electrons equally, but water gains a charge in liquid form.
Oxygen attracts shared electrons more strongly, and the molecule’s bent shape creates unequal charge distribution.
10. Water has a much higher boiling point than methane, even though both are small molecules. What is the main reason?
Methane molecules are polar and strongly repel one another.
Water molecules contain ionic bonds, whereas methane contains no bonds.
Liquid water has no molecular motion until it boils.
Water molecules form strong intermolecular hydrogen-bonding attractions.
11. A coastal city usually has smaller daily temperature swings than a nearby inland area. Which property of water contributes most to this pattern?
Water has a high specific heat capacity and changes temperature slowly.
Water conducts electricity without dissolved ions.
Water has a lower boiling point than most small molecules.
Water becomes less polar when exposed to sunlight.
12. A water strider can stand on a pond without immediately breaking through the surface. Which property provides the supporting effect?
Capillary action
Ice being less dense than liquid water
Surface tension produced by cohesive forces
Water’s ability to ionize salts
13. A paper towel draws water upward after one edge is dipped into a puddle. Which combination best explains this movement?
Low density and high vapor pressure
Adhesion to the fibers together with cohesion among water molecules
Freezing expansion and surface cooling
Repulsion between water and the towel fibers
14. Sweat can cool skin as it evaporates. Which explanation is most accurate?
Higher-energy molecules escape, carrying thermal energy away from the skin.
Water releases stored salt, which directly lowers skin temperature.
The coolest water molecules escape first and leave warmer molecules behind.
Evaporation converts water into ice before it enters the air.
15. Oil separates into a layer when mixed with water. Which explanation best accounts for this behavior?
Nonpolar oil cannot form sufficiently favorable interactions with polar water.
Oil is ionic and is repelled by both ends of a water molecule.
Oil breaks the covalent bonds inside water molecules.
Water can dissolve only substances that are denser than itself.
16. A burn from steam can transfer substantial energy when the steam condenses on skin. Which property of water is most relevant?
Its solid form is less dense than its liquid form.
Its phase change between liquid and gas involves a large amount of energy.
It has very low cohesion at all temperatures.
Its molecules become nonpolar in the gas phase.