ACIDS

Monoprotic acids -  one H+ ion per molecule acid. exp : HCl , HNO3

Diprotic acid - two H+ ions per molecule acid. exp :  H2SO4

ACIDS AND BASES

•The strength of an acid depends on the degree of ionisation the acid in water.

•

•A WEAK ACID is only partially ionised in water.

An example is ethanoic acid.

•every 100 CH3COOH molecules, only one of them ionises in water to form….

•

•CH3COOH ----------> H+ + CH3COO-

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TRANSITION ELEMENTS.............

Copper

Location on the Periodic Table

The transition elements are located in groups 3 to 12 of the periodic table.

Properties

Because they possess the properties of metals, the transition elements are also known as the transition metals. The transition elements have low ionization energies. They exhibit a wide range of oxidation states or positively charged forms. The positive oxidation states allow transition elements to form many different ionic and partially ionic compounds. Thus, the complexes form characteristic colored solutions and compounds. Complexation reactions sometimes enhance the relatively low solubility of some compounds.

Summary of Common Properties

• Low ionization energies
• Positive oxidation states
• Very hard
• High melting points
• High boiling points
• High electrical conductivity
• Malleable
• Five d orbitals become more filled, from left to right on periodic table

METALLOIDS........

Tellurium

Location on the Periodic Table

The metalloids or semimetals are located along the line between the metals and nonmetals in the periodic table. The metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium. Polonium is often considered a metalloid, too.

Properties

The electronegativities and ionization energies of the metalloids are between those of the metals and nonmetals, so the metalloids exhibit characteristics of both classes. Silicon, for example, possesses a metallic luster, yet it is an inefficient conductor and is brittle. The reactivity of the metalloids depends on the element with which they are reacting. For example, boron acts as a nonmetal when reacting with sodium yet as a metal when reacting with fluorine. The boiling points, melting points, and densities of the metalloids vary widely. The intermediate conductivity of metalloids means they tend to make good semiconductors.

Summary of Common Properties

• Electronegativities between those of metals and nonmetals
• Ionization energies between those of metals and nonmetals
• Possess some characteristics of metals/some of nonmetals
• Reactivity depends on properties of other elements in reaction
• Often make good semiconductors

BLUE COLOUR..........

This is COPPER (II) SULPHATE SOLUTION.

It"s BLUE SOLUTION. Please.........remind my colour...

I'm use as ELECTROLYTE in electrolysis process.

I can mantain my colour or bleach to colourless

depend on type of electrode used.

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.

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.

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

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.

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.

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