mercury-free school

Paracale National High School

Science and Math Month Celebration Teacher Mari

TOPICS…

What mercury isDifferent forms of mercurySources of mercury

Uses of mercury

Have you seen a mercury before?When and Where?

What did you do to it?

Mercury is a naturally occurring element.It cannot be created nor destroyed.

It is also called quicksilver or liquid silver.Mercury is very dense and can emit vapor at room temperature.

It is a heavy metal and can be found in different forms: elemental, inorganic and organic.

Elemental Mercury (a.k.a metallic mercury)

It is the pure, uncombined form of mercury. This is the kind you see inside thermometers. It is a shiny, silver-white metal that is liquid at room temperature. This form of mercury can evaporate to the air and create a mercury vapour that is hazardous to health. Mercury vapours are colorless and odorless which makes them hard to detect.

Elemental Mercury (a.k.a metallic mercury)

It is the pure, uncombined form of mercury. This is the kind you see inside thermometers. It is a shiny, silver-white metal that is liquid at room temperature. This form of mercury can evaporate to the air and create a mercury vapour that is hazardous to health. Mercury vapours are colorless and odorless which makes them hard to detect.

Inorganic Mercury Compounds or mercury salts

Are more commonly found in nature. Most of these are white powders or crystals (mercuric oxide and mercuric chloride) except for mercuric sulphide (red, turns black after exposure to light). Some inorganic mercury can also form a vapour but stay relatively shorter in the air.

Organic Mercury Compounds or organomercurials

Are formed when mercury is combined with carbon and other elements. There is a potentially large number of organic mercury compounds (dimeth-ylmercury, phenylmercury, ethylmercury) but the most common is methylmercury. Like inorganic mercury, they exist as “salts” except for dimethylmercury - a colorless liquid.

Natural Mercury occurs naturally in forms that are volatile, so mercury con-tinuously evaporates into the atmosphere, from both soil and water. Mercury-rich rocks and soils can lead to elevated mercury levels across wide areas. The weathering of rocks, volcanic activity and forest fires all contribute to the natural emission of mercury into the air.

Man-madeHuman activities release mercury found in raw materials, such as burning fossil fuels to generate electricity (especially coal-fired power plants), artisanal or small-scale gold mining, and metals production.Human activities release mercury that is intentionally used in products like batteries and processes such as incinerators.

Mercury has properties that have led to its use in many products.• It conducts electricity, forms alloy with

other metals, and expands in response to changes in temperature and pressure.• It also has antiseptic quality.

As a metal (among others):

• in manometers for measuring and controlling pressure• in thermometers• in fluorescent lamps• in dental amalgam fillings

• for extraction of gold and silver

As chemical compounds (among others):

• biocides in paper industry, paints and in seed grain• as antiseptics in pharmaceuticals• in skin whitening products• laboratory analyses reactants

• in batteries

• catalysts

Paracale National High School

Science and Math Month Celebration Teacher Mari

Thank you!