covalent bonding Flashcards
what happens when non-metal atoms bond?
they share pairs of electrons to make covalent bonds
how are the nuclei attracted to the shared electrons?
through strong electrostatic forces, making covalent bonds very strong
what does each covalent bond provide?
an extra shared electron
why type of covalent structure is H₂?
simple molecular
describe the forces within a simple covalent structure
strong covalent bonds between atoms but only weak intermolecular forces between molecules
why do simple molecular substances have a low boiling/melting point?
only the intermolecular forces, not the bonds, need to be broken which are very weak so the forces are easily overcome
what state are small molecular substances at room temp?
liquid or gas
what happens to the molecules as they get bigger?
the strength of intermolecular forces increase, so more energy is needed to overcome them and the melting and boiling points increase
why don’t molecular compounds conduct electricity?
don’t have an overall electric charge so no free ions
what does this bonding occur in?
non-metals
what particles are present in the bonding?
atoms that share electrons
can they conduct electricity?
no
what is a covalent bond?
a shared pair of electrons between two atoms
4 structure/properties of simple molecular covalent substances
-don’t conduct electricity
-small molecules
-weak intermolecular forces
-low boiling points
dot & cross, displayed formula for hydrogen
pg 54
dot & cross, displayed formula for chlorine
pg 54
dot & cross, displayed formula for oxygen
pg 54
dot & cross, displayed formula for ammonia
pg 53
dot & cross, displayed formula for nitrogen
pg 54
dot & cross, displayed formula for hydrogen chloride
pg 54
dot & cross, displayed formula for methane
pg 55
dot & cross, displayed formula for water
pg 55
what needs to be overcome to boil/melt a substance?
the intermolecular forces
relationship between size of molecule and intermolecular forces
the bigger the molecule, the stronger the intermolecular forces
