Properties of Water

Front

Covalent Bond Noun

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[koh-vey-luhnt bond]

Back

Covalent Bond

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A chemical bond formed between atoms that involves the sharing of electron pairs between them.

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Example: This image shows a water molecule where one oxygen atom shares electrons with two hydrogen atoms, forming the strong connections called covalent bonds.

Front

Polar Molecule Noun

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[poh-ler mol-i-kyool]

Back

Polar Molecule

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A molecule with an uneven distribution of electrical charge, resulting in a slightly positive end and a slightly negative end.

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Example: A water molecule is polar because it has an uneven distribution of charge, with a partial negative charge (δ-) on the oxygen atom and partial positive charges (δ+) on the hydrogen atoms.

Front

Hydrogen Bonding Noun

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[hahy-druh-juhn bon-ding]

Back

Hydrogen Bonding

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An attractive force between polar molecules containing hydrogen bonded to a highly electronegative atom like oxygen, nitrogen, or fluorine.

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Example: This diagram shows how water molecules stick together. The weak attraction between a hydrogen (H) on one molecule and an oxygen (O) on another is a hydrogen bond.

Front

Cohesion Noun

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[koh-hee-zhuhn]

Back

Cohesion

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The intermolecular attraction between molecules of the same substance, causing them to stick together tightly.

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Example: This diagram shows how water molecules stick to each other through hydrogen bonds, which is the force responsible for cohesion.

Front

Adhesion Noun

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[ad-hee-zhuhn]

Back

Adhesion

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The intermolecular attraction between molecules of different substances, causing them to stick firmly to one another.

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Example: This diagram shows water climbing a narrow tube because water molecules are attracted to the glass. This attraction between different substances (water and glass) is called adhesion.

Front

Surface Tension Noun

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[sur-fis ten-shuhn]

Back

Surface Tension

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A measure of the force required to stretch or break the surface of a liquid, caused by strong cohesive forces.

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Example: This diagram shows that water molecules at the surface are pulled together more tightly than molecules underneath, creating a strong 'skin' on the water.

Front

Meniscus Noun

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[muh-nis-kuhs]

Back

Meniscus

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The curve in the upper surface of a liquid close to the container's surface, caused by surface tension and adhesion.

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Example: This diagram shows that a meniscus is the curved upper surface of a liquid in a tube and demonstrates the correct eye-level technique for measurement.

Front

Universal Solvent Noun

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[yoo-nuh-vur-suhl sol-vuhnt]

Back

Universal Solvent

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A substance, such as water, that has the ability to dissolve a very large variety of other substances.

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Example: The polar water molecules surround and pull apart the positive (cation) and negative (anion) ions of a substance, causing it to dissolve.

Front

Solubility Noun

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[sol-yuh-bil-i-tee]

Back

Solubility

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The ability of a chemical substance, known as a solute, to dissolve in a solvent to form a solution.

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Example: This diagram shows a solute (sugar) being dissolved in a solvent (water) to form a solution, demonstrating the property of solubility.

Front

Specific Heat Noun

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[spuh-sif-ik heet]

Back

Specific Heat

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The amount of heat energy required to raise the temperature of a specific quantity of a substance by one degree.

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Example: This image compares a small amount of water to a large amount, showing that the large body of water does not heat up easily, illustrating water's high specific heat.