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Covalent bond resulting from the sharing of four electrons (two pairs) between two atoms.

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Flotation

Method by which hydrophobic (water-repelling) particles of an ore are separated from hydrophilic (water-attracting) particles of a metallurgical pretreatment process.

Electrolytic Cells

Electrochemical cells in which electrical energy causes nospontaneous redox reactions to occur. An electrochemical cell in which chemical reactions are forced to occur by the application of an outside source of electrical energy.

Quantum Numbers

Numbers that describe the energies of electrons in atoms, derived from quantum mechanical treatment.

Mass Action Expression

For a reversible reaction, aA + bB cC + dD the product of the concentrations of the products (species on the right), each raised to the power that corresponds to its coefficient in the balanced chemical equation, divided by the product of the concentrations of reactants (species on the left), each raised to the power that corresponds to its coefficient in the balanced chemical equation. At equilibrium the mass action expression is equal to K, at other times it is Q.[C]c[D]d [A]a[B]b = Q, or at equilibrium K.

Zinc

Discovered: known in India and China before 1500 and to the Greeks and Romans before 20 BC as the copper-zinc alloy brass
Origin: The name is derived from the German ‘Zink’.
Atomic no: 30
Mass No: 65
Description: A grey metal with a blue tinge. World production exceeds 7 million tons a year, and it is used to galvanise iron to prevent it rusting. It is also employed in alloys and batteries, and as zinc oxide to stabilise rubber and plastics. Zinc is essential for all living things, and is important for growth and development. The average human body contains about 2.5 grams and takes in about 15 milligrams per day. Some foods have above average levels of zinc, including herring, beef, lamb, sunflower seeds and cheese.

Atom

The smallest particle of an element.

Standard Electrodes

Half-cells in which the oxidized and reduced forms of a species are present at unit activity, 1.0M solutions of dissolved ions, 1.0atm partial pressure of gases, and pure solids and liquids.

Secondary Voltaic Cells

Voltaic cells that can be recharged, original reactanats can be regenerated be reversing the direction of the current flow.

Henry's Law

The pressure of the gas above a solution is proportional to the concentration of the gas in the solution.

Exothermicity

The release of heat by a system as a process occurs.