Chemistry for Health Sciences – Solutions, Water Properties & Concentrations

Vocabulary flashcards covering solutions, colloids, water chemistry terms, and concentration units for Chemistry for Health Sciences Quiz 6 and Midterm preparation.

Solution

A homogeneous mixture in which solute particles are molecular-size (<1 nm) and do not settle out; clear and stable (e.g., salt water).

Colloidal Dispersion

A mixture with dispersed particles 1–100 nm that scatter light (Tyndall effect) yet remain suspended (e.g., milk).

Suspension

A heterogeneous mixture containing visible particles >100 nm that settle upon standing (e.g., muddy water).

Emulsion

A colloidal dispersion of one liquid in another immiscible liquid, stabilized by an emulsifier (e.g., mayonnaise).

Gel

A colloidal system where a liquid phase is trapped within a solid network, giving a semi-solid texture (e.g., gelatin).

Aerosol

A colloidal dispersion of solid or liquid particles in a gas (e.g., fog, spray deodorant).

Polar Molecule

A molecule with an uneven distribution of electron density, creating partial positive and negative ends (e.g., H₂O).

Hydrogen Bond

An intermolecular attraction between a hydrogen attached to N, O, or F and a lone pair on another electronegative atom; responsible for many water properties.

Surface Tension

The elastic ‘skin’ at a liquid’s surface caused by cohesive hydrogen bonding; must be reduced for better wetting or cleaning.

Surface Tension Reducer (Surfactant)

A substance that lowers surface tension, enhancing wetting and cleansing; common in soaps and detergents.

Sodium Lauryl Sulfate

An anionic surfactant used in toothpaste and soaps to reduce water’s surface tension and aid cleaning.

Desiccant

A drying agent that removes moisture from its environment (e.g., silica gel packets).

Anhydrous

Describes a substance that contains no water molecules (water-free).

Hydrate

A crystalline compound that includes water molecules chemically bound within its structure (e.g., CuSO₄·5H₂O).

Hygroscopic

Having the ability to absorb moisture from the air (e.g., calcium chloride).

“Like Dissolves Like” Rule

Principle stating that polar solvents dissolve polar solutes and non-polar solvents dissolve non-polar solutes.

% w/v (percent weight/volume)

Concentration expressed as grams of solute per 100 mL of solution.

mg %

Milligrams of solute per 100 mL of solution; often used for blood or serum values (e.g., 90 mg % glucose).

% v/v (percent volume/volume)

Concentration expressed as milliliters of solute per 100 mL of solution.

C₁V₁ = C₂V₂

Dilution formula: product of initial concentration and volume equals product of final concentration and volume.

ppm (parts per million)

1 part solute per 1,000,000 parts solution; equivalent to mg solute per liter of water.

ppb (parts per billion)

1 part solute per 1,000,000,000 parts solution; equivalent to µg solute per liter of water.

Proof (Alcohol)

U.S. measure of ethanol content; Proof = 2 × % v/v alcohol (e.g., 40 % v/v = 80 proof).