✟ 神秘の科学城 ✟: 2017

SPM Form 4 Chemistry Notes — Chapter 5『5.1』Formation of Compounds

Stability of Noble Gases
  1. Noble gases are chemically non-reactive(inert)stable and exist as monoatomic gases.
  2. This is because the outermost occupied shell of all noble gases are full. They have very stable duplet / octet electron arrangement.
  3. Noble gases do not donate,receive or share electrons with other atoms.
  4. But the atoms of elements from Group 1 to Group 17 are tend to donate,receive or share electrons to achieve the stable duplet / octet electron arrangement and form chemical bonds.

Formation of compounds

  • A compound is a chemical substance which consist of two or more elements chemically bonded together.
  • A compound is in a more stable state than the elements comprising it.
Examples of natural compounds:

An ion is a positively-charged or negatively-charged particle formed after an atom donate / receive electrons. ( Cation=Positive ion ;Anion=Negative ion )


When an atomX donate 1 electronit form X+
When an atomX donate 2electronsit form X2+
When an atomX donate 3 electronsit form X3+

When an atomY receive 1 electronit form Y-
When an atomY receive 2electronsit form Y2-
When an atomY receive 3 electronsit form Y3-


SPM Form 4 Chemistry Notes — Chapter 4『4.1』The Periodic Table of Elements

Erm... 因为Periodic Table的历史来源很少会出题,所以我就Skip掉了,哈哈哈哈~~:P 但是还是鼓励大家去读一读比较好,因为有可能在Objective出现~ :D 只要refer各自的Chemistry课本都会有了哦!

Periodic Table

Groups and Periods in the Periodic Table


1) Each vertical column is called a group.
   a. There are 18 groups.
   b. Elements with similar chemical characteristics are grouped together.
   c. Each group contains elements with same number of valence electrons.

2) Each horizontal row is called a period.
   a. There are 7 periods.
   b. Each period contains elements with same number of shells which are filled with electrons.
   c. Each period contains elements with chemical and physical characteristics which change progressively from metal to non-metal.
d. Elements are arranged according to the order of their proton number which increases horizontally.


Group
Name of group
Group 1
Alkali metals
Group 2
Alkaline earth metals
Group 17
Halogens
Group 18
Noble gases
Group 3 to 12
Transition elements

Group 1 - very reactive metals
Group 18 - highly unreactive noble gases (chemically inert)
All transition elements - have metal characteristics.

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