Metallic/ore -- Eg. Carbon. Non metallic - Eg. Sulphur.

Silicates, Oxides, Sulphides, Halides, Carbonate.

1. Graphite and Diamond - both forms of carbon2. Sulphur and 3. Gold.

Aluminium, Copper, Lead, Iron.

Naturally occurring chemical compounds of fixed composition and Characteristics, physical  form and properties.

Coating of zinc over iron surface by hot dipping process is called so.

Mixtures of two or more metals, to make one new compound metal, used for special purposes to enhance the products' durability.

Hydrated Ferric Oxide.

Coating of Iron with metal or non-metals or by alloying.

A process of coating of another metal over iron is called so. The process is also called hot dipping.

Radon.

Chromium or Nickel.

The mass increases.

Addition of hydrogen and oxygen elements.

Water and oxygen.

When the metals are exposed to atomospheric conditions, they have a tendency to return to their original form. This change is called corrosion of Metals and while it is also called rusting of iron.

A by-product or form of Iron. In steel, the carbon content is brought down From 5% to 0.5 to 1.5%.

1. Quenching: Steel is heated to bright redness and then suddenly cooled in water or oil to make it extraordinarily hard and brittle.2. Tempering: The quenched steel is applied with a controlled heat of 250 to 325 degree to remove its brittleness, without affecting its hardness.3. Annealing: Steel is heated to a temperature well below red hot condition an then cooled to make it soft.

Arsenic - As, Astatine - At, Bromine - Br, Carbon - C, Chlorine - Cl, Fluorine - F, Hydrogen - H, Iodine - I, Nitrogen - N, Oxygen - O, Phosphorous - P, Selenium - Se, Sulphur - S, Tetterium - Te.

They are non-lustrous and are bad conductors of heat and electricity. The Melting point is lower than metals. They cannot be hammered into sheets Or drawn into wires.

Powders or gases except "bromine" which is liquid under normal conditions.

They are electro-negative elements which have a tendency to gain one or more electrons to form negative ions called "anions".

1. Calcination: Process of heating the concentrated ore in the absence of air.2. Roasting: Process of heating the ore in excess of air.3. Smelting: Process by which roasted ore is mixed with coke and heated In a furnace to obtain free metal.

Metallurgy.

Minerals from which metals are extracted.

Gold, Platinum and Silver. They are known as " Free Metals ".

Air (oxygen), Hydrogen, Halogens, Sulphur, Water, Acids etc., with the Extent of reaction of the metals vary in each metal.

Mercury and Galium.

1. Usually metals have the tendency to lose electrons and while reacting with Acids, usually replace Hydrogen in dilute non-oxidising acids like Hydrochloric Acid (HCl) and Sulphuric Acid, the exceptions being copper, Silver and Gold.2. Chlorides of metals are true salts and oxides of metals are usually basic.3. Hydrides of metals are ionic, unstable and reactive.

Elements which are hard, ductile, brittle and malleable, possesses luster and conduct heat and electricity are called so, with varying melting and boiling points.

About 80%.

Radon.

Hydrogen.

Osmium.

Lithium.

Astatine.

Nitrogen.

Oxygen.

An element whose atom has an incomplete d sub shell or which can give rise to cations with an incomplete d sub shell. Any of the metallic elements within groups 3 to 12 in the Periodic Table that have an incomplete inner electron shell and that serve as transitional links between the most and the least electro positive in a series of elements. They are characterized by multiple valences, colored compounds and the ability to form stable complex ions. Eg: Iron, copper, Nickel, Silver and Gold. Iron is a transitional metal from which steel is made.

There is no rigorous definition. On the basis of their general physical and Chemical properties, every element in the periodic table termed either a metal or non-metal. They are generally poor conductors of heat and electricity, dull and brittle, low in density, melting points and boiling points and have high electro negativity. Eg. Hydrogen, Carbon, Nitrogen, Phosphorous, Oxygen, Sulfur, Selenium etc.,

Chemical elements with similar properties. Under standard conditions, they are all odourless, colourless, mono-atomic gases with very low chemical reactivity. There are six of them : Helium, Neon, Argon, Krypton, Xenon and radioactive Radon.

Some elements have such properties based on which they are difficult to be Classified as metals or others. They may be solid and have metallic luster. But may not have the physical and chemical properties. Eg. Boron, Silicon, Germanium etc.,

Chemical elements that are good conductors of both electricity and heat and Forms cations and ionic bonds with non metals. Metals form the bulk of the Periodic table. Metals are usually inclined to form cations through electron Loss, reacting with oxygen in the air to form oxides over changing time Scales. Eg. Iron rusts over years, Potassium burning in seconds etc.,

They are grouped between atomic numbers 57 to 71 in the periodic table. They are termed so because the lighter elements in the series are chemically similar to Lanthanum. They have a single valence electron in the d shell. Eg: Lanthanum, Cerium, Praseodymium, Neodymium etc.,

A series of non metal elements. They are group of halogens in the periodic table which contains elements in all familiar states of matter at standard temperature. Owing to their high reactivity, the halogens are found in the environment only in compounds or as ions. Eg. Flourine, Chlorine, Bromine etc.,

They are naturally occurring and share similar properties. They are all reactive metals under standard conditions silver colored soft metals which react readily with halogens to form ionic salts, but not as rapidly as the alkali metals to form strong alkaline hydroxides. Eg. Gerlyllium, Magnesium, Calcium etc.,

Elements categorized under this category are radio active and release energy Upon radioactive decay. Naturally occurring Uranium, Thorium and Synthetically produced Plutonium are the abundant actinides on Earth.

They are naturally occurring elements, like, Lithium, Sodium, Potassium, Rubidium, Caesium and Francium. Of these, Francium is the second most rare element. They are highly reactive and are never found in elemental forms in nature. Because of this, they are generally stored in oil or kerosene. These metals are mostly silver coloured. They have low melting points and densities.

Actinium, Alkali Metals, Alkaline Earth Metal, Halogens, Lanthanides, Metal, Metalloid, Noble Gases, Non-metal and Transition Metals.

Are chemical isotopes that may or may not be radioactive but if radioactive, Have half lives too long to be measured.

Isotopes are variants of atoms of a particular chemical element which have differing numbers of neutrons. Eg. Carbon 12, 13 and 14. They are isotopes of the element carbon, having the same atomic number 6, but their neutron numbers are 6,7, and 8 respectively.

Ununoctium.

Seven.

Henri Moseley a British Physicist.

Periods.

1869 - Dimitry Mendeleev - Russia.

Hydrogen - Atomic No.1 meaning 1 proton and 1 electron.

URANIUM - with Atomic No. 92. It is also the heaviest naturally occurring Element with 92 protons, 92 electrons and 146 neutrons. All elements heavier than Uranium are man made and are produced in nuclear reactors or Accelerators or isolated from debris of atomic explosions - Transuranics.

1. Metals: Eg: Lead, Gold, Mercury etc.,2. Non-Metals: Eg: Chlorine, Bromine, Carbon etc.,

The arrangement of elements in increasing order of Atomic Numbers, Clubbing together elements with similar properties is called Periodic Table.

Neptunium - Atomic Number 93 - 1940.

Made by nuclear bombardment, and are called "Transuranics".

In an element, the number of electrons is always equal to the number of Protons and this number is called the Atomic Number.

About 118. Of which 94 are naturally occurring and the rest are made.

It consists of a central nucleus, made up of protons which are positively charged and neutrons which are neutral particles, surrounded by orbiting electrons. Atoms of different elements, differ from one another in the number of protons and neutrons in the nucleus and the number of electrons surrounding the nucleus.

The smallest neutral particle of matter which may have independent existence.

John Dalton.

Smallest fragment of an element that can take in chemical action.

The simplest form of matter, composed of atoms, having identical number of Protons in each nucleus.