Ionic Bonds
Ionic bonds are formed when metal elements bind with nonmetallic elements. Metals are the elements that tend to release a number of electrons to achieve stability. After removing their electrons, the metal elements will turn into positive ions.
Example:
Na ==> Na+ + e
Al ==> Al3+ + 3e
Alkaline, alkaline earth and some members of group 13 element (aluminum) are examples of metals. In general, atoms that tend to release electrons usually have valence electrons less than 4.
Non-metals are the elements that tend to capture a number of electrons to achieve stability. When this element captures some electrons, the element will turn into negative ions.
Example:
Cl + e ==> Cl-
N + 3e ==> N3-
In general, atoms that tend to capture electrons usually have more than 4 valence electrons.
When a positive ion meets a negative ion, there will be an attraction between the two ions called the electrostatic force. This electrostatic forces (the tensile force between two different charged ions) are then called ionic bonds.
Positive and negative ions can form when there is an electron handover between a metal and a nonmetal element. The metal atom releases several electrons to form a positive ion. These released electrons will be captured by non-metallic atoms so they turn into negative ions. When two ions with different charges are formed, there will be a pull force between the two ions. This force then forms an ionic bond on the compound.
Example:
Formation of ionic bonds in NaCl.
NaCl is an ionic compound formed from sodium and chlorine atoms. Sodium has 11 electrons and chlorine has 17 electrons.
Electron configuration:
Na = 2 8 1 ==> valence electrons = 1
Cl = 2 8 7 ==> valence electrons = 7
Because it has 1 valence electron, sodium will tend to release one of its electrons to form a positive ion (Na +). The electrons that have been released by sodium are captured by chlorine so they become stable (have 8 valence electrons) and form a negative ion (Cl-).
The Na + ion will then attract Cl- ions to form ionic bonds in the NaCl compound. In summary, you can see the process below:
Na ==> Na+ + e
Cl + e ==> Cl-
Na + Cl ==> Na+Cl- (NaCl)
Determining the formula of the ionic compound
To understand how to write the formula of ionic compounds formed by two elements, study the following example!
Example:
Find the formula of the compound formed by:
1. Lithium and oxygen (Li atom number = 3 and O = 8)
2. Aluminum and Chlorine (Al atomic number = 13 and Cl = 17)
Answer:
1. Lithium and oxygen
To determine the formula of ionic compounds formed from two elements, first, determine the positive and negative ion charges of each atom.
The ion charge can be known from its atomic electron configuration. As mentioned above:
Configuration:
Li = 2 1 ==> valence electrons = 1
O = 2 6 ==> valence electrons = 6
Lithium will release 1 of its outer electrons so that it becomes stable to form Li + ions. While oxygen will be stable if it receives two electrons to form O2- ions. In order for the transfer of electrons to occur, it takes two Li atoms to bind with one oxygen. This is because a single Li atom can only contribute 1 electron to an oxygen atom.
In summary:
2Li ==> 2Li+ + 2e
O + 2e ==> O2-
2Li + O ==> 2Li+ O2- (Li2O)
The formula of the ionic compound formed is Li2O.
2. Aluminum and Chlorine
Configuration:
Al = 2 8 3 ==> valence electrons = 3
Cl = 2 8 7 ==> valence electrons = 7
Because it has 3 valence electrons, Al will tend to form positive ions with a +3 charge (Al3 +). While Cl, which has 7 valence electrons, tends to capture one electron to form a negative ion with a charge of -1 (Cl-1).
It takes 3 Cl atoms to bind to one Al. This is because Al requires 3 electrons to stabilize.
In summary:
Al ==> Al3+ + 3e
3Cl + 3e ==> 3Cl-
Al + 3Cl ==> Al3+ 3Cl- (AlCl3)
The formula of ionic compounds formed is AlCl3.
Example:
Na ==> Na+ + e
Al ==> Al3+ + 3e
Alkaline, alkaline earth and some members of group 13 element (aluminum) are examples of metals. In general, atoms that tend to release electrons usually have valence electrons less than 4.
Non-metals are the elements that tend to capture a number of electrons to achieve stability. When this element captures some electrons, the element will turn into negative ions.
Example:
Cl + e ==> Cl-
N + 3e ==> N3-
In general, atoms that tend to capture electrons usually have more than 4 valence electrons.
When a positive ion meets a negative ion, there will be an attraction between the two ions called the electrostatic force. This electrostatic forces (the tensile force between two different charged ions) are then called ionic bonds.
Positive and negative ions can form when there is an electron handover between a metal and a nonmetal element. The metal atom releases several electrons to form a positive ion. These released electrons will be captured by non-metallic atoms so they turn into negative ions. When two ions with different charges are formed, there will be a pull force between the two ions. This force then forms an ionic bond on the compound.
Example:
Formation of ionic bonds in NaCl.
NaCl is an ionic compound formed from sodium and chlorine atoms. Sodium has 11 electrons and chlorine has 17 electrons.
Electron configuration:
Na = 2 8 1 ==> valence electrons = 1
Cl = 2 8 7 ==> valence electrons = 7
Because it has 1 valence electron, sodium will tend to release one of its electrons to form a positive ion (Na +). The electrons that have been released by sodium are captured by chlorine so they become stable (have 8 valence electrons) and form a negative ion (Cl-).
The Na + ion will then attract Cl- ions to form ionic bonds in the NaCl compound. In summary, you can see the process below:
Na ==> Na+ + e
Cl + e ==> Cl-
Na + Cl ==> Na+Cl- (NaCl)
Determining the formula of the ionic compound
To understand how to write the formula of ionic compounds formed by two elements, study the following example!
Example:
Find the formula of the compound formed by:
1. Lithium and oxygen (Li atom number = 3 and O = 8)
2. Aluminum and Chlorine (Al atomic number = 13 and Cl = 17)
Answer:
1. Lithium and oxygen
To determine the formula of ionic compounds formed from two elements, first, determine the positive and negative ion charges of each atom.
The ion charge can be known from its atomic electron configuration. As mentioned above:
- If the number of valence electrons of an atom is less than 4, then it tends to form a positive ion. The positive charge formed is equal to the number of electrons it releases.
- If the number of valence electrons of an atom is more than 4, then it tends to form a negative ion. The negative charge formed is equal to the number of captured electrons.
Configuration:
Li = 2 1 ==> valence electrons = 1
O = 2 6 ==> valence electrons = 6
Lithium will release 1 of its outer electrons so that it becomes stable to form Li + ions. While oxygen will be stable if it receives two electrons to form O2- ions. In order for the transfer of electrons to occur, it takes two Li atoms to bind with one oxygen. This is because a single Li atom can only contribute 1 electron to an oxygen atom.
In summary:
2Li ==> 2Li+ + 2e
O + 2e ==> O2-
2Li + O ==> 2Li+ O2- (Li2O)
The formula of the ionic compound formed is Li2O.
2. Aluminum and Chlorine
Configuration:
Al = 2 8 3 ==> valence electrons = 3
Cl = 2 8 7 ==> valence electrons = 7
Because it has 3 valence electrons, Al will tend to form positive ions with a +3 charge (Al3 +). While Cl, which has 7 valence electrons, tends to capture one electron to form a negative ion with a charge of -1 (Cl-1).
It takes 3 Cl atoms to bind to one Al. This is because Al requires 3 electrons to stabilize.
In summary:
Al ==> Al3+ + 3e
3Cl + 3e ==> 3Cl-
Al + 3Cl ==> Al3+ 3Cl- (AlCl3)
The formula of ionic compounds formed is AlCl3.
0 Response to "Ionic Bonds"
Post a Comment