Nursing the Nurse

Description: A substance that is dissolved in solution and 

some of its molecules split or dissociate into electrically 

charged atoms or ions 

Measurement 

a. The metric system is used to measure volumes of 

fluids—liters (L) or milliliters (mL).

b. The unit of measure that expresses the combining 

activity of an electrolyte is the milliequivalent 

(mEq).

c. One milliequivalent (1 mEq) of any cation will 

always react chemically with 1 mEq of an anion.

d. Milliequivalents provide information about the 

number of anions or cations available to combine 

with other anions or cations.

Properties of Electrolytes and Their Components

ATOM
An atom is the smallest part of an element that still
has the properties of the element.
The atom is composed of particles known as the
proton (positive charge), neutron (neutral), and
electron (negative charge).
Protons and neutrons are in the nucleus of the atom;
therefore, the nucleus is positively charged.
Electrons carry a negative charge and revolve around
the nucleus.
As long as the number of electrons is the same as the
number of protons, the atom has no net charge; that is,
it is neither positive nor negative.
Atoms may gain, lose, or share electrons and then are
no longer neutral.

MOLECULE
A molecule is two or more atoms that combine to form a
substance.

ION
An ion is an atom that carries an electrical charge because it
has gained or lost electrons.

Some ions carry a negative electrical charge and some carry
a positive charge.

CATION
A cation is an ion that carries a positive charge and has
given away or lost electrons.
The result is fewer electrons than protons, and the result is a
positive charge.

ANION
An anion is an ion that has gained electrons and therefore
carries a negative charge.
When an ion has gained or taken on electrons, it assumes a
negative charge and the result is a negatively charged ion.