Ionic Bonding
2. Short Answer Test – Click Here
3. Kahoot! based on Video – Click Here
IONIC BONDING
Ionic bonding is a specific type of bonding that occurs between oppositely charged ions. Positively charged ions join with negatively charged ions to form Ionic bonds.
Ionic bonding is a specific type of bonding that occurs between oppositely charged ions. Positively charged ions join with negatively charged ions to form Ionic bonds.
Atoms on the far left column of the periodic table become stable by losing one electron and so form 1+ ions. The atoms in the second colomn can attain stability by losing 2 electrons and so form 2+ ions and the atoms in the 2nd last column of the periodic table can become stable by gaining an electron and forming 1- ions.
Ionic bonds are formed when these oppositely charged ions join together. For example, sodium ions can join with chloride ions to form Sodium Chloride – Table salt.
Atoms that have a greater charge – like Calcium with a 2+ charge can form ionic bonds with multiple 1- ions. So for example, Calcium would bind to 2 chloride ions. Each positive charge in the Calcium is able to hold onto one chloride ion.
A 3+ Ion like aluminum could therefore form ionic bonds with 3 chloride ions.
Unlike covalent bonds, where there is a sharing of electrons between 2 atoms, in ionic bonding there is not a sharing of electrons. Rather, one atom holds an extra electron and is negatively charged and the other atom is missing an electron and so is positively charged and the opposite charges of the two atoms – hold the atoms together – like a magnet. Therefore, Ionic bonds are like magnetic bonds created by two oppositely charged atoms whereas covalent bonds are created when 2 atoms share electrons with each other.
Most of the ions found in our body however, do not form ionic bonds. The reason for this is that most ions remain stable in the body’s watery fluid. The body is 60% water and ions dissolve in this watery environment and remain separated in their ionic form.
IONIC BONDING IN THE BODY
The main exception to this is bones and teeth. In bones and teeth Calcium ions join with hydroxide ions and phosphate ions through ionic bonding. The positive charges of calcium create magnetic links with the negative charges of hydroxide and phosphate ions. This combination of calcium, phosphate and hydroxide ions is referred to as hydroxyapatite. This hydroxyapatite creates the hard cyrstalline structure of bone and teeth.
Ionic bonds are found in the molecules that create the structure of BONES AND TEETH. However, outside of bones and teeth ionic bonds are rare.
In summary – ionic bonding is special type of bonding that occurs between oppositely charged ions. Unlike covalent bonds which are a sharing of electrons and are common in the molecules throughout the body ionic bonds are found mainly in the hard crystalline structures of bones and teeth.