Properties of Water Vocabulary Flashcards

A set of vocabulary flashcards covering key chemical and biological concepts related to the properties of water, thermal energy, solutions, and plant stomata.

Polar Molecule

A molecule with an uneven distribution of electric charge due to polar covalent bonds, resulting in a partially positive end and a partially negative end.

Hydrogen Bond

A weak electrostatic attraction formed when a partially positive hydrogen atom of one polar molecule is attracted to a partially negative atom of another polar molecule.

Cohesion

The phenomenon of like molecules staying linked to one another by mutual attraction, such as water molecules holding together via hydrogen bonding.

Adhesion

The clinging of one substance to a different substance, such as water molecules sticking to cell walls or hydrophilic plant surfaces via hydrogen bonds.

Capillary Action

The movement of liquid upward through a narrow space against the force of gravity, facilitated by the combined forces of cohesion and adhesion.

Transpiration

The movement of water from plant roots up through water-conducting cells and its eventual evaporative loss through leaf stomata, providing cooling to plant tissues.

Surface Tension

A measure of how difficult it is to stretch or break the surface of a liquid, caused by the cohesive pull of surface molecules toward the interior of the liquid.

Stomata

Microscopic pores on the surfaces of plant leaves that enable gas exchange, allowing $CO_2$ to enter and $O_2$ along with water vapor to exit.

Guard Cells

Specialized epidermal cells that flank stomata and regulate their opening and closing to balance photosynthesis with water loss prevention.

Kinetic Energy

The energy of motion associated with the movement of atoms and molecules.

Thermal Energy

The total kinetic energy associated with the random movement of atoms or molecules in a body of matter, which depends on the matter's volume.

Temperature

A measure reflecting the average kinetic energy of the molecules in a body of matter, independent of its volume.

Heat

Thermal energy in transfer from one body of matter to another, moving spontaneously from a warmer object to a cooler object.

Calorie (cal)

The amount of heat energy required to raise the temperature of $1\,g$ of water by $1\,^\circ C$, or released when $1\,g$ of water cools by $1\,^\circ C$.

Kilocalorie (kcal)

A unit of heat energy equal to $1,000\,cal$, defined as the quantity of heat needed to raise the temperature of $1\,kg$ of water by $1\,^\circ C$.

Joule (J)

An energy unit equal to $0.239\,cal$, where $1\,cal = 4.184\,J$.

Specific Heat

The amount of heat that must be absorbed or lost for $1\,g$ of a substance to change its temperature by $1\,^\circ C$.

Heat of Vaporization

The quantity of heat energy a liquid must absorb for $1\,g$ of it to be converted from a liquid to a gaseous state.

Evaporative Cooling

The decrease in temperature of a liquid's remaining surface during evaporation, occurring because the molecules with the highest kinetic energy escape into the gas phase.

Solution

A completely homogeneous mixture composed of two or more substances.

Solvent

The dissolving agent of a solution, which dissolves the solute.

Solute

The substance that is dissolved in a solvent to form a solution.

Aqueous Solution

A solution in which water serves as the solvent.

Hydration Shell

The sphere of oriented water molecules surrounding each dissolved ion or polar solute molecule in an aqueous solution.

Hydrophilic

Describing any substance that has an affinity for water, whether or not it dissolves in water.

Hydrophobic

Describing nonionic and nonpolar substances that lack an affinity for water and cannot form hydrogen bonds, causing them to repel water.

Tradescantia zebrina

Commonly known as Inchplant or Zebra Plant, a species whose leaf epidermis is used in lab wet mounts to observe stomata and guard cells under a microscope.