Covalent Bonding Flashcards
What is a covalent bond?
A strong bond that forms when a pair of electrons is shared between two atoms, that gives the atoms full outer shells.
What are 6 examples of simple molecular substances (joined by covalent bonds)?
Hydrogen, H2 Hydrogen Chloride, HCl Water, H2O Oxygen, O2 Methane, CH4 Carbon dioxide, CO2
What is the general size of a simple molecule?
10 ^-10 m.
What are simple molecular substances made up of?
Made up of molecules containing a few atoms joined by covalent bonds.
How strong are the covalent bonds between atoms in a molecule?
The covalent bonds are very strong between atoms in a molecule.
How strong are the forces of attraction between these molecules?
Despite the covalent bonds between atoms being strong, the forces of attraction between the molecules are very weak.
What do you need to do to melt or boil a simple molecular compound?
You only need to break the feeble intermolecular forces and NOT the the covalent bonds.
How high are the melting and boiling points of simple molecular compounds, and why?
The melting and boiling points are very low, because the molecules are easily parted from each other.
What state are most molecular substances at room temperature?
Liquids or gases.
As molecules get bigger, what happens to the strength of the intermolecular forces?
As molecules get bigger, the strength of the intermolecular forces increases, so more energy is needed to break them, so the melting and boiling points increase.
Do molecular compounds conduct electricity?
No, because they don’t contain any free electrons or ions.
What are polymers?
Molecules made up of long chains of covalently bonded carbon atoms. They’re formed when lots of small molecules called monomers join together.
