Magnesium Nitrate
By: Lexi DeFalco
Honors Chemistry
Magnesium is the sixth most common element on Earth (5). It was isolated in 1808 by Sir
Humphry Davy and named for the area Magnesia in ancient Greece (1). It is the seventh most
abundant element in Earth’s crust and large amounts are found dissolved in the oceans waters
(5). There is almost as much magnesium in the world as iron and sulfur combined (1). Its atomic
number is 12 and is in the family Alkaline Earth Metals, making it very reactive (5). Some of
magnesium’s compounds include magnesium chloride, magnesium oxide, magnesium
phosphate, and, the compound I researched, magnesium nitrate (1).
Magnesium nitrate is a white, odorless, crystalline solid (2). It is only available in the
liquid or solid hydrated form. This is because the hydrous (something that contains water) form
is not stable under normal conditions (6). Its melting point is around 90 degrees Celsius or 190
degrees Fahrenheit. It decomposes at about 330 degrees Celsius or 620 degrees Fahrenheit (4).
Magnesium nitrate is made up of 4.72% Hydrogen, 9.48% Magnesium, 10.93% Nitrogen, and
74.88% Oxygen (2). Its molecular weight is 148.32 g/mol (6).
Magnesium nitrate has many uses. It is contained in inks, toners, and fertilizers. It is a
common antifreeze and de-icing chemical. It can also be used as a water treatment chemical or as
an intermediate to synthesize, or combine, other substances (6). Finally, magnesium nitrate can
be used in fireworks and pyrotechnics (3). It is found in caverns and mines as nitromagnesiate.
The nitromagnesiate forms as a result of the leaching process of bat guano (feces) (8). This is
when the feces of the bat is filtered. However, magnesium nitrate has many side effects.
Symptoms may include coughing, shortness of breath, skin irritation with redness or pain, or
1
mild irritation to the nucleus membranes. Ingestion of a large dose can cause vomiting,
weakness, convulsions, dizziness, or collapse (3). To be safe, whenever around magnesium
nitrate, always wear safety goggles, and protective gloves and clothing (6).
Although not combustible, magnesium nitrate can accelerate the burning of combustible
materials. If mixed with phosphorus, tin chloride, or other reducing agents, it may react
explosively. Also, if the combustible material is finely divided, an explosion may occur. Finally,
and explosion may also result if there is prolonged exposure to heat or fire. Magnesium nitrate
can produce toxic oxides of nitrogen if heated to decomposition. It has also been known to
undergo spontaneous decomposition in dimethylformamide (3).
Magnesium nitrate is an ionic compound. An ionic compound is an attraction between
positive (cation) and negative (anion) ions. Most of the time the cations are metals and the anions
are nonmetals. Electrons are transferred between these metals and nonmetals. This makes
magnesium nitrate have an ionic bond. That is because cations and anions have opposite charges
so they attract each other. The electrostatic force is an attraction between two polar opposites.
These forces that hold the two ions together are called ionic bonds. Most ionic compounds are
crystalline solids at room temperature, are hard and brittle, and have high melting points. They
can conduct an electric current when dissolved in water or melted (7). The chemical formula for
magnesium nitrate is Mg(NO3)2 (2).A chemical formula shows the numbers and kinds of atoms
in the smallest representative unit (7).
Magnesium nitrate is deliquescent (having a tendency to become liquid) and is very
soluble in both water and ethanol (3). Its water solubility is 125 g/100 ML (6). It is not harmful
to aquatic life and is not a known carcinogen. It is also not bio accumulative or biodegradable.
2
Magnesium is a very interesting element to study, with its high level of reactivity and
lightness, making it easy to use in everyday things. Without magnesium nitrate we would not
have things such as inks, fertilizers, and even pyrotechnics. This white, crystalline solid is a big
component of chemistry.
3