Covalent bonding Flashcards
What type of elements take part in covalent bonding?
Non-metal atoms
How is a covalent bond formed?
A covalent bond is formed when two positive nuclei are held together by their common attraction for a shared pair of electrons
Give the definition for a single covalent bond
A single covalent bond consists of one shared pair of electrons
Give the definition for a double covalent bond
A double covalent bond consists of two shared pair of electrons
Give the definition for a triple covalent bond
A triple covalent bond consists of three shared pair of electrons
Name the 7 diatomic elements
Nitrogen, hydrogen, oxygen, fluorine, chlorine, bromine, and iodine
How many types of covalent structures are there?
There are two: discrete molecular and giant network
Describe the structure of a covalent molecular substance
Covalent molecular substances are made up of molecules joined together by weak forces of attraction (van der Waals)
Explain, in detail, why covalent molecular substances have low melting and boiling points
During melting and boiling it is only these weak forces of attraction called van der Waals forces that are broken. They require little energy to break
Describe a covalent network structure and explain why they have high melting and boiling points
A covalent network consists of a giant 3 dimensional network of atoms joined together by strong covalent bonds. They have very high MP because the network of strong covalent bonds is not easily broken as lots of energy is needed to break covalent bonds
Explain why covalent substances do not conduct in any state
Covalent substances do not conduct electricity in any state because there are no charged particles which are free to carry the current
Are covalent molecular substances soluble in water?
Some covalent molecular substances are soluble in water and other covalent substances may dissolve in other substances such as ethanol or acetone
Do covalent network substances dissolve?
No, covalent network substances do not dissolve in any solvents
How do you figure out what state a substance is at room temperature?
If MP is BELOW RT and the BP is ABOVE RT then it is a LIQUID at RT.
If MP is ABOVE RT then it is a SOLID at RT
if BP is BELOW RT then it is a gas at RT
