Chemistry

Experiment: To prepare ethene and examine its properties

Ethene gas is prepared by dehydrating ethanol (drug found in alcoholic drinks). Ethene is a colourless gas with a sweet smell. It is a insoluble in water but can dissolve in organic solvents. Main Chemicals required Ethanol – CH3CH2OH Aluminium oxide – a white powder in appearance – Al2O3 Procedure   Pour small… Continue Reading →

Some famous scientists associated with chemistry

The Atom John Dalton – proposed a theory about atoms in 1808. William Crookes – investigated what happens when electricity passed through gases. J.J Thomson – discovered the electron. Robert Millikan – measured the size of the charge on the electron. Ernest Rutherford – worked on radioactivity and lead the discovery of… Continue Reading →

The Electron: Crash Course Chemistry

The story of the electron and describes how reality is a kind of music, discussing electron shells and orbitals, electron configurations, ionization and electron affinities, and how all these things can be understood via the periodic table.

Elements & the Periodic Table

An element is a substance that cannot be broken down into simpler substances by chemical means. Pure substances can be also compounds. But compounds can be chemically broken down to the elements of which they are made. Elements cannot be broken down into simpler substances. Each element has a symbol and an unique atomic number. (Know the symbols of elements with… Continue Reading →

Tests for Anions

Chloride ion Test: Add a few drops of Silver Nitrate (AgNO3) solution. Observation: A white precipitate is formed. Sulfate ion Test: Add BaCl2 solution to a solution of the solid. Observation: A white precipitate is formed. Carbonate ion Test: Add dilute HCL to the solid. Observation: Fizzing. The gas that is given off turns limewater milky. Nitrate ion Test: Brown ring test. Add freshly prepared FeSO4 solution to the solid…. Continue Reading →

The first 36 elements of the periodic table

H – Hydrogen He – Helium Li – Lithium Be – Beryllium B – Boron C – Carbon N – Nitrogen O – Oxygen F – Fluorine Ne – Neon Na – Sodium Mg – Magnesium Al – Aluminium Si – Silicon P – Phosphorus S – Sulfur Cl – Chlorine Ar – Argon K – Potassium Ca – Calcium Sc – Scandium Ti – Titanium V – Vanadium Cr – Chromium Mn – Manganese… Continue Reading →

Experiment: To prepare ethyne and examine its properties

Ethyne gas is prepared by the reaction of water with calcium carbide (CaC2). Ethyne gas is a colourless gas. Main Chemicals required Calcium Carbide (CaC2) [also known as calcium dicarbide] – A white/gray solid Acidified copper (II) sulfate solution Water Procedure Set up the apparatus as shown in the diagram. Place few pieces of… Continue Reading →

Organic Compounds – Tetrahedral & Planar carbons

Tetrahedral carbon compounds In saturated organic compounds, all of the carbon atoms are tetrahedral. Chloroalkanes A chloroalkane is an alkane in which one or more hydrogen atoms are replaced with chlorine atoms. Chloroform () is an example of a chloroalkane. Chloroalkane’s main uses: For removing oil and grease marks from machinery and in… Continue Reading →

Organic Chemistry – Fuels & Heats of Reaction

Organic chemistry is the chemistry of carbon containing compounds. A hydrocarbon is a substance that contains only carbon and hydrogen. There are three main hydrocarbons on the course – alkanes, alkenes and alkynes. A homologous series is a series of compounds: of similar chemical type. that show gradual change in their physical properties. all are prepared in a similar way. have a common… Continue Reading →

The Periodic Table Groups

A group (also known as a family) is a vertical column in the periodic table of elements. The alkali metals – Group I Very reactive soft metals. Increases in reactivity down the group. They have low densities. They react quickly with oxygen in air and with water. Alkali metals are stored in oil to prevent reactions… Continue Reading →