Chapter 2, Lesson 2: Water and Mixtures

Flashcards from Chapter 2, Lesson 2 of McGraw Hill Anatomy and Physiology, Ninth Edition, by Kenneth S. Saladin.

Mixtures

Substances that are physically blended but not chemically combined; most are body fluids with water

Properties of water

Solvency, cohesion, adhesion, reactivity, thermal stability

Solvency

The ability to dissolve other chemicals; water is the universal this

Hydrophilic substances

Substances that dissolve in water; molecules that are this are polarized or charged (like sugar)

Hydrophobic

Substances that do not dissolve in water; molecules that are this are nonpolar or neutral (like fats)

Hydration spheres

Ionic bonds being overpowered by hydrogen bonds from water

Adhesion

The tendency of one substance to cling to another; water does this in membranes

Cohesion

The tendency of like molecules to cling to each other; water does this due to its hydrogen bonds and makes surface tension

Chemical reactivity

The ability to participate in chemical reactions; water does this into H⁺ and OH^-

Heat capacity

The amount of heat needed to raise the temperature of 1 gram of a substance by 1 degree C

Calorie

The base unit of heat that raises the temperature of 1 gram of water by 1 degree C

Thermal stability

The ability to stabilize the temperature of its surroundings; water can absorb high levels of heat and remove calories

Solution

Consists of the solute particles mixed with a more abundant substance called the solvent; particles are under 1 nm, do not scatter light, will pass through membranes, and won’t separate on standing

Colloid

Consists of mixtures of protein and water; particles are 1-100 nm, scatter light, do not pass through membranes, and remain permanently mixed

Suspension

A mixture of particles that are bigger than 100 nm, too large to pass through membranes, cloudy or opaque, and will separate on standing

Acid

A liquid that donates protons through releasing H⁺ ions; the pH is less than 7 and H⁺ > OH^-

Base

A liquid that accepts protons by accepting H⁺ ions or donating OH^- ions; the pH is greater than 7 and H⁺ < OH^-

pH

The measure of acidity derived from the molarity of H⁺, 7 is neutral when H⁺ = OH^-

Weight per volume

Weight of solute in a given volume of solution; milligrams per deciliter (mg/dl) is common in biology

Percentages in solutions

May be weight (solid) or volume (liquid) per volume of solution

Electrolyte measurement

Measured in equivalents (Eq); 1 Eq = amount needed to neutralize 1 mole of H⁺ or OH^- ions