Atoms of elements in Group 1，2 and 13 with valence electron 1，2 and 3 will form POSITIVE ION （+，2+ and 3+）by donating electrons to attain a stable duplet/octet electron arrangement.
Na = 2.8.1 (proton no.和electron no.一样)Na+ = 2.8 (因为捐了1 electron，是好人所以positively charge)
Mg = 2.8.2 (proton no.和electron no.一样)Mg2+ = 2.8 (因为捐了2 electrons，所以2+)
Formation of Negative Ions / Anions (Non-Metals)
Atoms of elements in Group 15，16 and 17 with valence electron 5，6 and 7 will form NEGATIVE ION （-，2- and 3-）by receiving electrons to attain a stable duplet/octet electron arrangement.
O = 2.6 (还欠2 electrons)O2- = 2.8 (所以当从别的atom拿走2 electrons，就变negatively charge)
Cl = 2.8.7 (还欠1 electron)Cl- = 2.8.8 (因为从别的atom拿走1 electron)
Name for Atoms and Ions of Non-Metal Elements
Atoms
|
Ions
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Oxygen, O
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Oxide, O2-
|
Fluorine, Fl
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Fluoride, Fl-
|
Chlorine, Cl
|
Chloride, Cl-
|
Bromine, Br
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Bromide, Br-
|
Iodine, I
|
Iodide, I-
|
Positively charge的ions，名字的结尾是“ium”
Negatively charge的ions，名字的结尾是“ide”
至于要如何分辨Metals和Non-Metals，可以参考我的Periodic Table
Formation of Ionic Bonds
- Formed through the transfer of electrons between atoms of metal and non-metals. 『如果一个compound是由金属和非金属结合而成，那么一定会有转移electon』
- Metal atom donates an electron to form a positive ion (cation). 『好人捐东西，所以+』
- Electrons are transferred from metal atoms to non-metal atoms.
- Non-metal atom accepts electron to form a negative ion (anion). 『拿了别人的东西，所以-』
- The cation and anion are attracted to each other by strong electrostatic forces. 『正负互相吸引，这个吸引力称为electrostatic forces』
- The ionic bond is formed.
Formation of Sodium Chloride
- The electron arrangement of the sodium atom is 2.8.1.
- A sodium atom donates 1 electron to achieve the stable octet electron arrangement, 2.8.
- A sodium ion is formed. (Na → Na+ + ē)
- The electron arrangement of the chlorine atom is 2.8.7.
- A chlorine atom accepts 1 electron from the sodium atom to achieve the stable octet electron arrangement, 2.8.8.
- A chloride ion is formed. (Cl + ē → Cl-)
- The sodium ion and chloride ion are attracted to each other by a strong electrostatic force.
- An ionic compound sodium chloride, NaCl is formed. (The strong electrostatic force between the oppositely-charge ions is called ionic bond or electrostatic bond)
Formation of Calcium Oxide
- The electron arrangement of the calcium atom is 2.8.8.2.
- A calcium atom donates 2 electrons to achieve the stable octet electron arrangement, 2.8.8.
- A calcium ion is formed. (Ca → Ca2+ + 2ē)
- The electron arrangement of the oxygen atom is 2.6.
- An oxygen atom accepts 2 electrons from the calcium atom to achieve the stable octet electron arrangement, 2.8.
- An oxide ion is formed. (O + 2ē → O2-)
- The calcium ion and oxide ion are attracted to each other by a strong electrostatic force.
- An ionic compound calcium oxide, CaO is formed.
Formation of Magnesium Fluoride
- The electron arrangement of the magnesium atom is 2.8.2.
- A magnesium atom donates 2 electrons to achieve the stable octet electron arrangement, 2.8.
- A magnesium ion is formed. (Mg → Mg2+ + 2ē)
- The electron arrangement of the fluorine atom is 2.7.
- A fluorine atom accepts 1 electron from the magnesium atom to achieve the stable octet electron arrangement, 2.8.
- A fluoride ion is formed. (Fl + ē → F-)
- The magnesium ion and fluoride ion are attracted to each other by a strong electrostatic force.
- An ionic compound magnesium fluoride, MgF2 is formed.
Formation of Lithium Oxide
- The electron arrangement of the lithium atom is 2.1.
- A lithium atom donates 1 electron to achieve the stable duplet electron arrangement, 2.
- A lithium ion is formed. (Li → Li+ + ē)
- The electron arrangement of the oxygen atom is 2.6.
- An oxygen atom accepts 2 electrons from the lithium atom to achieve the stable octet electron arrangement, 2.8.
- An oxide ion is formed. (O + 2ē → O2-)
- The lithium ion and oxide ion are attracted to each other by a strong electrostatic force.
- An ionic compound lithium oxide, Li2O is formed.
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人，要学会聆听，听智者之言可以启迪智慧，听批评之言可以反躬自省。
即使记忆总有一天会消逝，就让我们一起留下欢乐的一点一滴、美好的回忆~ :D