Water Quiz 3.1-3.2

Solvent

A liquid substance capable of dissolving other substances

Surface Tension

A measure of how difficult it is to stretch or break the surface of a liquid

Solute

A substance that is dissolved in a solution.

Adhesion

An attraction between molecules of different substances. Adhesion of water by hydrogen bonds to the molecules of the cell wall helps counter the downward pull of gravity.

Evapotative Cooling

As a liquid evaporates the surface of a liquid cools down. This occurs because the the "hottest" molecules, those with the greatest kinetic energy, are more likely to leave as gas.

Cohesion

Attraction between molecules of the same substance. Cohesion due to Hydrogen bonding contributes to the transfer of water and dissolved nutrients against gravity in plants.

Hydrophilic

Having an affinity for water. Substances that can form Hydrogen bonds.

Hydrophobic

Having an aversion to water; tending to coalesce and form droplets in water. These are non-ionic and non-polar

Floating of Ice on Liquid Water

Ice floats in liquid water because hydrogen bonds in ice are more "ordered," making ice less dense than water. If ice sank, all bodies of water would eventually freeze solid, making life impossible on Earth.

What is the shape water like?

It is shaped like a V, with two Hydrogen atoms joined with one Oxygen atom by single covalent bonds.

Is oxygen or hydrogen more electronegative?

Oxygen, because the electrons spend more time closer to oxygen than to hydrogen; these are also called polar covalent bonds.

specific heat of water

The specific heat of a substance is defined as the amount of heat that must be absorbed or lost for 1g to change 1C. Water's is 1g to 1C.

Water is a polar molecule.

The unequal sharing of electrons make water a polar molecule, meaning that its overall charge is unevenly distributed.

Why is it cooler by the lake in summer?

Water has a higher heat capacity than soil and rock, so the ocean takes much longer to heat and to cool than the land. Coastal areas will generally have more moderate temperatures than inland areas because of the heat capacity of the ocean.

capilary action

When liquid goes up a narrow tub against the force of gravity. Capillary action occurs when adhesive forces outweigh cohesive forces. ... The narrower the vessel or tube, the greater the effect of capillary action.

Ice

When water freezes, water molecules form a crystalline structure maintained by hydrogen bonding. Solid water, or ice, is less dense than liquid water. Ice is less dense than water because the orientation of hydrogen bonds causes molecules to push farther apart, which lowers the density.

aqueous solution

a solution in which water is the solvent

water is a versatile solvent

due to its polarity, which allows it to form hydrogen bonds easily

Liquid

water molecules are constantly bonding and breaking