(lab) pre-lab exercise 2-1 key terms

pH unit

The measure of the relative acidity or alkalinity of a solution.

True solutions

The solutes of true solutions are very small, usually in the form of individual atoms and molecules. Consequently, they are not visible to the naked eye, do not settle out, and do not scatter light. usually transparent

polar covalent bond

A covalent bond in which electrons are not shared equally charge unbalanced among atoms

solution

A homogenous mixture of gases, liquids, or solids

solubility

A measure of how much solute can dissolve in a given solvent at a given temperature and pressure.

Suspension

A suspension is a heterogeneous mixture.

chemical reaction

Process in which molecules are formed, changed, or broken down.

Hydrophobic

Water fearing refers to molecules, or portions of molecules, that interact only with nonpolar molecules.

nonpolar covalent bond

a covalent bond in which the bonding electrons are shared equally by the bonded atoms resulting in a balanced distribution of electrical charge

deoxyribonucleic acid (DNA)

a nucleic acid found in all living cells; it carries the organism's hereditary information.

enzyme

a protein that acts as a biological catalyst to speed up a chemical reaction.

base

a substance capable of binding with hydrogen ions; a proton acceptor

acid

a substance that releases hydrogen ions when in solution (compare with Base); a proton donor

solvent

the substance in which the solute dissolves. (usually liquid) The solvent is the substance present in the greatest amount in a solution.

solute

the substance that is dissolved in a solution. substance present in the smallest amount in a solution.

buffer

chemical substance or system that minimizes changes in pH by releasing or binding hydrogen ions.

ionic bond

complete transfer of electrons separate ions (charged particles) form

denatured

loss of an enzyme's normal shape so that it no longer functions; caused by a less than optimal pH and temperature

hydrophilic

refers to molecules, or portions of molecules, that interact with water and charged particles.