GOOD LUCK FOR ALL MY STUDENT
DO THE BEST IN SPM...
Sunday 25 November 2012
Wednesday 30 May 2012
About Electrochemistry??????
Different atoms pull on bonding electrons to differing degrees, and this difference is the pivotal property in determining whether a covalent or ionic bond is formed. When one atom has a much higher pull on bonding electrons than its partner, electron transfer occurs, and an ionic compound is formed. When both atoms have similar attractions for the bonding electrons, they'll share them more equitably and a covalent compound is formed.
Elements can be ranked by their relative attraction for bonding electrons. The more different their ranks, the more likely the bond is to be ionic.
Elements by their ability to attract bonding electrons - Linus Pauling and others considered several elemental properties to develop a consistent ranking scheme. Pauling used the element's ionization energy and electron affinity to predict how it will behave in a bond. The more energy it takes to pull off the outer electron of an atom, he reasoned, the less likely it is to allow another atom to take those electrons. The more energy the atom releases when it gains an electron, the more likely it is to take electrons from another atom in bonding. These two energies were used to compute a numerical score called anelectronegativity. Electronegativity ranks the element's tendency to attract electrons and acquire a more negative charge in a bonding situation.
Electronegativity will increase going left to right across the periodic table. Fluorine's high nuclear charge coupled with its small size make it hold onto bonding electrons more tightly than any other element. Lithium has a lower nuclear charge and is actually larger than fluorine. Its valence electron is not tightly held and it tends to surrender it in chemical bonds.
How are electronegativity values used? Consider coupling two fluorine atoms together. Even though each atom has a high attraction for bonding electrons, both attract them equally. The electronegativity difference between the atoms is zero, and the bond ispure covalent.
Oxidation Number of Xenon
Oxidation Numbers and Position in the Periodic Table
Compounds of xenon are by far the most numerous of the rare-gas compounds.
With the exception of XePtF6, rare-gas compounds have oxidation numbers of +2, +4, +6, and +8, as shown by the examples cited in the table below.
Compounds of Xenon and their Oxidation Numbers
Compound | Oxidation Number | Compound | Oxidation Number | ||||
XeF+ | +2 | XeO3 | +6 | ||||
XeF2 | +2 | XeOF4 | +6 | ||||
Xe2F3+ | +2 | XeO2F2 | +6 | ||||
XeF3+ | +4 | XeO3F- | +6 | ||||
XeF4 | +4 | XeO4 | +8 | ||||
XeOF2 | +4 | XeO64- | +8 | ||||
XeF5+ | +6 | XeO3F2 | +8 | ||||
XeF6 | +6 | XeO2F4 | +8 | ||||
Xe2F11+ | +6 | XeOF5+ | +8 |
What is Noble Gas????
Discovery of Noble Gases
In 1892 Lord Rayleigh found that oxygen was always 15.882 times more dense than hydrogen, no matter how it was prepared.
When he tried to extend this work to nitrogen, he found that nitrogen isolated from air was denser than nitrogen prepared from ammonia.
William Ramsey attacked this problem by purifying a sample of nitrogen gas to remove any moisture, carbon dioxide, and organic contaminants.
He then passed the purified gas over hot magnesium metal, which reacts with nitrogen to form the nitride.
3 Mg(s) | + | N2(s) |  | Mg3N2(s) |
When he was finished, Ramsey was left with a small residue of gas that occupied roughly 1/80th of the original volume.
He excited this gas in an electric discharge tube and found that the resulting emission spectrum contained lines that differed from those of all known gases.
After repeated discussions of the results of these experiments, Rayleigh and Ramsey jointly announced the discovery of a new element, which they named argon from the Greek word meaning the "lazy one" because this gas refused to react with any element or compound they tested.
Argon did not fit into any of the known families of elements in the periodic table, but its atomic weight suggested that it might belong to a new group that could be inserted between chlorine and potassium.
Shortly after reporting the discovery of argon in 1894, Ramsey found another unreactive gas when he heated a mineral of uranium.
The lines in the spectrum of this gas also occurred in the spectrum of the sun, which led Ramsey to name the element helium (from the Greek helios, "sun").
Experiments with liquid air led Ramsey to a third gas, which he named krypton ("the hidden one").
Experiments with liquid argon led him to a fourth gas, neon ("the new one"), and finally a fifth gas,xenon ("the stranger").
These elements were discovered between 1894 and 1898. Because Moissan had only recently isolated fluorine for the first time and fluorine was the most active of the known elements.
Ramsey sent a sample of argon to Moissan to see whether it would react with fluorine. It did not.
The failure of Moissan's attempts to react argon with fluorine, coupled with repeated failures by other chemists to get the more abundant of these gases to undergo chemical reaction, eventually led to their being labeled inert gases.
The development of the electronic theory of atoms did little to dispel this notion because it was obvious that these gases had very symmetrical electron configurations.
As a result, these elements were labeled "inert gases" in almost every text book and periodic table until about 30 years ago.
In 1962 Neil Bartlett found that PtF6 was a strong enough oxidizing agent to remove an electron from an O2 molecule.
PtF6(g) | + | O2(g) |  | [O2+][PtF6-](s) |
He therefore predicted that PtF6 might also react with Xe. When he ran the reaction, he isolated the first compound of a Group VIIIA element.
Xe(g) | + | PtF6(g) | [Xe+][PtF6-](s) | |
A few months later, workers at the Argonne National Laboratory near Chicago
Since that time, more than 200 compounds of Kr, Xe, and Rn have been isolated.
No compounds of the more abundant elements in this group (He, Ne, and Ar) have yet been isolated.
However, the fact that elements in this family can undergo chemical reactions has led to the use of the term rare gases rather than inert gases to describe these elements.
Thursday 24 May 2012
Me and SKP6024
ICT IN CHEMISTRY EDUCATION & MYSELF
MY 1st impression of this Course????
The first impression when i heard and overview what is all about this course, really made me nervous and I thought it take a long take to make all the assignments. I just thought am i can go through all this for one semester. First time in this class, the beauty lady appears and introduced her as CIK HAJAH ASMAYATI..She is so kind and very friendly and also all the friends in this course very friendly of each other. I cannot wait for the next class to see my colleague and CIK ASMAYATI.....
Tuesday 15 May 2012
Selamat Hari Guru 2012: Guru inovatif Melonjakkan Transformasi Pendidikan Negara
Guru Inovatif Melonjakkan Transformasi Pendidikan Negara
Kita berbicara tentang inovasi
Ciptaan baharu gaya hidup kini
Meningkatkan Produktiviti Terkini
Bangun, beranikan terima seruan
Mendidik, memimpin penuh berwawasan
Menciptakan kreativiti
Melahirkan Guru Inovatif
c/o
Sahutlah cabaran, perubahan
Daulatkan Bidang Pendidikan,
Guru Inovatif Melonjakkan
Transformasi Pendidikan Negara
Malaysia Ku tercinta
Kita berbicara tentang inovasi
Ciptaan baharu gaya hidup kini
Meningkatkan Produktiviti Terkini
Tiada pernah jemu tiada putus asa
Sedia menimba ilmu di mana saja
Binakanlah keyakinan
Merentasi segala halangan
Saturday 21 April 2012
About Learning & Teaching
Learning is a process of active
engagement with experience. It is what people do when they want to make sense
of the world. It may involve the development or deepening of skills, knowledge,
understanding, awareness, values, ideas and feelings or an increase in the
capacity to reflect. (Bround M., Reiss M., 2004). While, teaching has a
scientific basis, its practices are based on research and scientific evidence.
Teaching is also an art based on teachers’ experiences and the wisdom of
practice. (Arends R., 2004). Today’s school require teachers who have a
repertoire of effective strategies so need of all children can be met. The aims
of chemistry curriculum for secondary school are to provide students with the
knowledge and skills in chemistry and technology and enable to solve problems
and make decision in everyday life based on scientific attitudes and noble
values. So, in teaching and learning teachers need to emphasise the mastery of
skills together with the acquisition of knowledge and the inculcation of noble
values and scientific attitudes. Today have so many literature reviews about
theories, techniques, methods, and approaches in teaching and learning
chemistry.
Wednesday 18 April 2012
Teaching Philosophy
A teacher's personal philosophy of education is a critical element in his or her approach to guiding children along the path of enlightenment.
FALSAFAH KURIKULUM KIMIA
Pendidikan di Malaysia adalah suatu usaha berterusan untuk memperkembangkan lagi potensi individu secara menyeluruh dan bersepadu supaya dapat melahirkan insane yang seimbang, harmoni dan bermoral tinggi. Hasrat ini termaktub dalam Falsafah Pendidikan Kebangsaan. Dalam merealisasikan pembinaan insane seperti yang dihasratkan itu, pendidikan sains dalam Kurikulum Standard Sekolah Rendah (KSSR) dan Kurikulum Standard Sekolah Menengah (KSSM) diwacanakan agar berupaya membentuk rakyat Malaysia yang seimbang daripada segi jasmani, emosi, rohani dan intelek.
Mata pelajaran Kimia adalah program dua tahun untuk pelajar Tingkatan empat dan lima sekolah menengah atas. Ia dirancang untuk membolehkan pelajar memahami bidang kimia dengan lebih mendalam daripada aspek teori, konsep serta aplikasinya dalam kehidupan harian. Pemerolehan dan
penguasaan pengetahuan dan kemahiran berkaitan dengan kimia menyediakan pelajar untuk menangani perubahan dan menyumbang ke arah pengurusan diri dan alam sekitar dengan penuh tanggungjaw ab demi kesejahteraan hidup manusia. Mata pelajaran ini menyediakan pelajar dengan asas pendidikan kimia untuk melanjutkan pelajaran ke bidang kimia, bidang yang memerlukan pengetahuan dan kemahiran berkaitan dengan kimia serta ke kerjaya yang berkaitan dengan sains dan teknologi. Ianya selaras dengan Falsafah Pendidikan Sains Negara.
TUJUAN KURIKULUM KIMIA
Kurikulum Kimia bertujuan untuk melahirkan murid yang mempunyai pengetahuan dan kemahiran dalam bidang kimia dan mampu mengaplikasikan pengetahuan dan kemahiran ini berlandaskan sikap saintifik dan nilai murni untuk membuat keputusan dan menyelesaikan masalah dalam kehidupan harian. Justeru, murid mempunyai landasan kimia untuk melanjutkan pelajaran di samping mengamalkan budaya sains dan teknologi ke arah pembentukan masyarakat bersifat ikram, dinamik, progresif, bertanggungjawab terhadap alam sekeliling dan mengagumi penciptaan alam.
1. Memperoleh pengetahuan kimia dan menghubungkaitkan pengetahuan ini dengan fenomena alam semula jadi dan pengalaman harian.
2. Memahami pengetahuan kimia yang berkaitan dengan perkembangan bidang sains dan teknologi, pengurusan alam semula jadi dan sumbernya serta proses industri dalam pelbagai bidang.
3. Menguasai kemahiran berfikir dan kemahiran saintifik.
4. Mengaplikasikan pengetahuan dan kemahiran secara kritis dan kreatif berasaskan sikap saintifik dan nilai murni dalam penyelesaian masalah, membuat keputusan dan mengkonsepsikan.
5. Mengamalkan sikap saintifik dan nilai murni.
6. Menilai maklumat berkenaan dengan bidang kimia dengan bijak dan berkesan.
7. Menangani cabaran dalam dunia sains dan teknologi dan bersedia memberi sumbangan kepada perkembangan sains dan teknologi.
8. Menyedari kepentingan pengurusan alam semula jadi serta sumbernya dengan bijaksana untuk keberterusan hidup manusia sejagat.
9. Menghargai sumbangan sains dan teknologi terhadap pembangunan negara dan kesejahteraan manusia sejagat.
10. Menyedari bahawa penemuan melalui penyelidikan sains adalah usaha manusia berasaskan kemampuan akal untuk memahami fenomena alam ke arah mencapai kesejahteraan hidup manusia sejagat.
Saturday 24 March 2012
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