|What is an acid?|
|Question Date: 2015-04-30|
To understand what an acid is, it’s
important to know what protons and electrons are.
Atoms are made of positively charged protons
and negatively charged electrons. Something is
an acid if when you add it to water, it has a
“loose” proton which is peeled off by the water
molecules. For a substance that’s really
acidic like hydrochloric acid, the water molecules
pretty much take of its loose protons. When
another chemical comes into contact with water
that has an extra proton, it may take the proton
back in a chemical reaction. When something rusty
is dipped into water with an acid in it, the
excess protons on the water will basically pull
the rust off the metal. Acids are also really
important in biology, for instance, in your
stomach is really acidic which helps pull apart
the food you eat into smaller parts the body can
use. Acids can also be dangerous like if you get
them on your skin, they will react with the
molecules that make up your skin and damage it.
Substances can be classified as acidic, basic
or neutral depending on their position on the pH
The pH scale is 0-14.
A pH of 0-7 is acidic and a pH of 7-14 is basic.
A pH of exactly 7 is neutral.
Most acids contain the element, hydrogen. This
is not a strict rule in chemistry, but it is true
for most substances that we call acids. The pH
scale is a measure of the “power of hydrogen,” and
it describes the relative acidity of difference
Acids are “corrosive,” which means they
dissolve metal and also can burn your skin or eyes
if it is strong enough (very low pH). Our bodies
handle small amounts of weak acids (moderate pH)
like vinegar or lemon juice. These foods have a
sour taste, which is characteristic of acids.
An acid is any chemical compound that can
dissociate into an anion (a molecule with a
negative charge) and a positively-charged proton,
when dissolved in a solvent (like water).
Basically, it's a salt, but the cation is a proton
instead of a larger cation.
An acid is a molecule that in solution will
produce hydrogen ions (H+). In contrast, a
base is a molecule that will produce hydroxide
ions (OH-). An acid can be identified by it's
physical and chemical properties. For example,
acids taste sour, they have a pH less than 7, and
they produce hydrogen gas under a chemical
reaction with a metal. If you had orange juice
this morning, you drank an acid. Other acids
include lemons and vinegar.
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