Vocabulary
Acids and Bases
Solution
A mixture of two or more substances that is homogeneous (the same) throughout.
Solute
The substance present in the smallest (smaller) amount in a solution. It could also be
the substance that changes state when a solution is prepared, for example: the solid
that dissolves in a liquid to form a liquid solution.
Solvent
The substance present in the largest (larger) amount in a solution. It could also be the
substance that does not change state when a solution is prepared, for example: the
liquid that acts as the dissolver when a solid is added to form a liquid solution. Water
is frequently the solvent in many liquid solutions.
Dissociate
When a chemical compound (an ionic compound) is dissolved in a solvent, usually
water, and separates into two or more ions. The ions in the compound stop
associating.
Ion
An atom, or group of atoms, whose number of electrons does not equal its number of
protons. An ion has a negative or positive charge. A cation is positively charged and
an anion is negatively charged.
Acid
A chemical compound that dissociates into hydrogen ion(s) and a negatively charged
ion when mixed with water
Base
A chemical compound that dissociates into hydroxide ion(s) and a positively charged
ion when mixed with water
Hydrogen Ion
When an acid is mixed with water, it dissociates into a negatively charged ion and a
hydrogen ion, H+. A hydrogen ion is a hydrogen atom that has lost 1 electron, so only
the nucleus and its single proton remain.
Hydroxide ion
When a base is mixed with water, it dissociates into positively charged ion and a
hydroxide ion, OH-. A hydroxide ion is a water molecule that has lost a hydrogen ion,
H+ , leaving its electron.
pH scale
A linear scale from 0 to 14 that is a measure of the hydrogen ion concentration in a
solution.
Concentration
The ratio of the amount of solute to the volume of solvent in a solution.
Concentration is usually expressed as a certain mass or volume of solute that is
dissolved in 1 milliliter, 100 milliliters, or in 1 liter.
Dilution
Process of preparing a less concentrated solution by adding more solvent.
Neutralization
When an acid and a base react to form water molecule(s) and reduce the hydrogen ion
concentration. The pH of the solution gets closer to pH 7.