Reactions Study Guide

Chemical Reaction

Matter changes from one compound to another with different properties.

Physical Reaction

Matter changes its appearance but does not change on a molecular level.

Biochemical Reaction

A chemical change that happens in a cell.

Reactant

Chemical(s) before a reaction takes place.

Product

Chemical(s) after a reaction takes place.

Law of Conservation of Mass

Matter cannot be created or destroyed.

Density

The amount of mass per volume of a substance (unit = g/mL or g/cm^3).

Viscosity

The ability of a liquid substance to flow, can be high or low.

Solid

Molecules held together in a fixed pattern.

Liquid

Molecules that are close together but free to move.

Gas

Molecules that are widely separated.

Solute

The substance being dissolved in a solution.

Solvent

The substance doing the dissolving in a solution.

Aqueous Solution

When water is the solvent.

pH

Potential hydrogen, acids and bases.

Acid

When the ratio of H+ is greater than OH- in an aqueous solution.

Base

When the ratio of OH- is greater than H+ in an aqueous solution.

Decomposition

Breakdown of larger molecules into its parts.

Synthesis

Combination of smaller molecules into a larger.

Single Replacement

One molecule remains and another is recombined.

Double Replacement

Both molecules rearrange and swap components.