Convalent Bonding Flashcards
What is a covalent bond?
When non-metal elements react with non-metal elements they usually form covalent compounds. A covalent bond is one where electrons are shared between atoms (in contrast to an ionic bond which is formed when electrons are transferred from one atom to another).
Definition of a covalent bond
The electrostatic attraction between a shared pair of electrons and the two adjacent nuclei (of the atoms involved).
Draw the covalent bond between two hydrogen atoms
N/a
Draw PCl5 covalently bonded
N/a
What is a single bond?
A single bond is 1 shared pair of electrons (Cl — Cl)
What is a double bond?
2 shared pair of electrons (O == O)
What is a triple bond?
3 shared pairs of electrons (N=_ N
Draw the displayed formula and dot and cross diagram of ethene (C2H4)
N/a
What bonds can carbon form?
4 single bonds
2 single bonds + 1 double bond
2 double bonds
1 single bond + 1 triple bond
What bonds can nitrogen form?
3 single bonds
1 single bond + 1 double bond
1 triple bond
What bonds can oxygen form?
2 single bonds
1 double bond
What bonds can fluorine form?
1 single bond
Draw the dot and cross diagram and displayed formula for CH3CO2H
N/a
Two types of covalent compound structures
- simple covalent
- giant
Structure of covalent compounds
The majority of compounds that contain covalent bond adopt a simple covalent structure. This is the reason there exist as gases and liquids at room temperature and not solids.
Within the molecule, the atoms are held together by strong covalent bonds. However, between the molecules, there are only weak intermolecular forces. The intermolecular forces between the molecules are much weaker than the covalent bonds within a molecule. When a molecule is broken down, it is these intermolecular forces that are overcome.
Do covalent molecules conduct electricity?
No
Fluorine is a relatively small molecule. How can we guess the state of matter of fluorine at room temperature?
Fluorine is small, hence it is weak intermolecular forces, meaning it must be a fluid a room temperature. We can say that it is a gas.
What do smaller covalent molecules have?
This means that most simple molecular substances are liquids or gasses at room temperature. The smallest molecules will have the lowest boiling points as they have the weakest intermolecular forces.
