To do well for your O level Chemistry examination, you need to be familiar with one of the fundamental topics – Chemical bonding.
In addition to knowing the types of bonds different compounds have, you also need to know how their structure and bonding relates to their properties!
Generally, there are 3 types of bonds:
1. Ionic bond (Giant ionic/crystal lattice structure)
2. Covalent bond (simple molecular / giant macromolecule)
3. Metallic bond (giant metallic lattice)(Pure chem.)
As a guideline,
1) metal and non-metals react to form ionic compounds,
2) non-metals react to form covalent compounds,
3) metallic bonds are found WITHIN a metal. (NOT BETWEEN 2 METALS!!!)
Today, I’d like to share with you a structured question on Chemical Bonding.
Question 1 (Pure/Combined)
Briefly explain why Magnesium Oxide has a higher melting point than Sodium Chloride.
Magnesium oxide contains Mg2+ and O2- ions while sodium chloride contains Na+ and Cl- ions. The electrostatic forces of attraction are stronger in MgO than NaCl due to the larger positive and negative charged ions. More energy is needed to overcome these stronger electrostatic forces of attraction hence m.p. of MgO is higher.
Bear in mind, the strength of an ionic bond increases with increasing charge!
I hope you managed to learn something new today! Do feel free to share this with your friends who might be struggling with O level Chemistry!