Monday, April 18, 2011

ELEMENT OF THE DAY..........SULPHUR


Sulfur is an element that many people recognize in its pure form as a yellow solid. The element exists free in nature and forms many important compounds, such as sulfuric acid, hydrogen sulfide and several vital enzymes. Some well-known odors, including skunk, rotten egg, onion and grapefruit, are due to the presence of sulfur compounds. The element is essential for life, yet many sulfur compounds are toxic.


Properties: Sulfur has a melting point of 112.8°C , boiling point of 444.674°C, specific gravity of 2.07 at 20°C, with a valence of 2, 4, or 6. Sulfur is a pale yellow, brittle, odorless solid. It is insoluble in water, but soluble in carbon disulfide. Multiple allotropes of sulfur are known.

Uses: Sulfur is a component of gunpowder. It is used in the vulcanization of rubber. Sulfur has applications as a fungicide, fumigant, and in the making of fertilizers. It is used to make sulfuric acid. Sulfur is used in the making of several types of paper and as a bleaching agent. Elemental sulfur is used as an electrical insulator.

Saturday, March 19, 2011

STRUCTURE FORMULAE.....

Structural formulas show every atom and every bond, as well as the unshared electron pairs found in a molecule. Atoms are represented by their atomic symbol. Bonds are represented by solid black lines.

Tuesday, February 22, 2011

JUST LIKE SOLAR SYSTEM..........



MODERN ATOMIC MODEL
By James Chadwick

SUBATOMIC :

PROTON (+)
NEUTRON (no charge)
Both located in nucleus

ELECTRON (-)
Round nucleus at certain orbit

RELATIVE MASS OF :

PROTON - 1
NEUTRON -1
ELECTRON -1/1840
almost 0

Wednesday, February 9, 2011

FRACTIONAL DISTILLATION



Fractional distillation is the separation of a mixture into its component parts, or fractions, such as in separating chemical compounds by their boiling point by heating them to a temperature at which several fractions of the compound will evaporate.

Tuesday, January 18, 2011

What is Naphthalene?


Diagram of naphthalene heating process

Melting point is the temperature where the solid become liquid.

Naphthalene (ubat gegat)

The melting point of naphthalene is 78
degree Celsius.

Wednesday, January 5, 2011

WHAT IS CHEMISTRY?


Chemistry is the science concerned with the composition, structure, and properties of matter, as well as the changes it undergoes during chemical reactions.

WELCOME 2011....YEAR OF EXCELLENT


Selamat datang tahun baru 2011.

selamat datang juga buat student2 saya yang baru naik form 5.

bersedialah dengan segala kelengkapan untuk pergi berperang...

sebelum itu sudi lah menerima sedikit sebanyak tunjuk ajar

sebagai bekalan dimedan perang...............SPM 2011 pasti cemerlang.

cg. Izad