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Extraction Of Metals

Definition of metals Metals are defined chemically as elements which have the following general qualities [1]: They conduct electricity They have a metallic lustre They are malleable and ductile. They form cations. They have basic oxides. Occurrence In universe In seawater and in earth’s crust, metals are usually present in the form of ores or … Read more

Halide Test

What is halide? A halide is a dual-phase in which one part is a halogen atom and the other part is an element or radical that is less electronegative or more electropositive than that of halogen to make a fluoride, chloride, bromide, iodide, astatide or hypothetically tennesside compound. Under suitable conditions, the alkali metals combine … Read more

Flame Test

Introduction The flame test is one of the most commonly used analytical processes in chemistry. It is widely used to detect and analyze the presence of certain elements in the given salt or compound. Primarily, the flame test detects the presence of metal ions in a compound, and as ions of each element have a … Read more


Hydroxide Definition Hydroxide is a negatively charged ion comprised of oxygen and hydrogen atom bonded covalently with each other. It normally attached with a positively charged metal to form a base. e.g. NaOH. In aqueous solution, these base give hydroxide ion OH–. According to Arrhenius substance that forms hydroxide ion in aqueous solution is base. … Read more

Transition Metals

Introduction to transition metal Most of the d block elements in the periodic table are transition metal elements. The following figure shows the d-block elements in periodic table. Not all the d-block elements are transition metals. Transition metals are only those d-block elements which contain unfilled d-orbital even after losing electron to form ion. Transition … Read more

Oxidation State

Oxidation State Definition Oxidation number of an atom is the charge that atom would have if the compound is composed of ions. It represents the number of electrons an atom gains or losses when bonded with other atom in a molecule. As for example the oxidation number of chromium in CrCl3 is +3. Rules to … Read more

Oxidation Reduction

Oxidation Reduction┬áReaction Definition An oxidation-reduction (redox) is a chemical reaction involving transfer of electrons between two species. An oxidation-reduction reaction is any chemical reaction where the oxidation number of a molecule, atom, or ion changes – by gaining or losing an electron. The redox reactions are very common and vital to the basic functions life, … Read more