chemistry - covalent bonding: semester 2

what does covalent bonding contain?

polar covalent and non-polar covalent

intramolecular forces > 

forces between atoms to form compounds 

covalent bond >

a sharing of electrons between non-metal atoms

when is a covalent bond formed?

when atoms share one or more pairs of electrons

polar covalent >

electrons are not shared equally

non-polar covalent > 

electrons are shared equally 

electronegativity >

the ability of an atom to attract electrons to itself

less than 0.5 >

covalent

0.5-2.0 > 

polar covalent 

more than 2.0 >

ionic

what do covalent bonds break into?

its ions

what are covalent bonds at room temperature? 

liquids, soft solids, or gasses

what are some examples of soft solids?

water, sugar, carbon dioxide, and graphite

what are the melting points and boiling points of covalent compounds?

low

how do covalent compounds conduct electricity? 

poorly in all phases 

can covalent compounds conduct electricity?

yes but very poorly

are covalent compounds soluble in water?

mostly not

what are examples of polar compounds that are soluble? 

ethanol, ammonia 

bond energy > 

the energy required to break a chemical bond 

what does bond energy correspond to?

bond length

what is the relationship of a bond energy? 

inverse 

what does the short bond equal?

higher energy

what is included in the covalent compounds?

diatomic elements

diatomic elements > 

molecules formed of only two atoms of the same element

diatomic elements are all _______

gases 

what do diatomic elements form?

molecules

what are the diatomic molecules?

H(2), N(2), O(2), F(2), Cl(2), Br(2), I(2)

what do diatomic elements form?

non-polar 

diatomic elements are never found in _________ singularly

nature

what are diatomic elements ALWAYS?

non-polar

molecule =

diatomic elements and it forms a bond with itself 

polyatomic ions >

group of covalently bonded non-metal atoms

what characteristics does polyatomic ions?

molecular and ionic

the charge result form and ______ of electrons (-) or a ___________ or electrons (+)

excess, shortage 

description of covalent bonds >

• non-metal

• shared electrons

• low melting and room temperature boiling points

• liquids and gases at room temperature

• relatively soft (organic compounds)

• weak bonds

• does not normally conduct electricity

• insoluble in water

• electron orbitals overlap

what are two exceptions of the octet rule?

hydrogen and helium

bonding electrons >

two electrons holding the element together

lone pairs > 

tow electrons connected to only one atom 

if carbon is the compound, where does it go?

in the center

what always connects to the central atom?

terminal atoms 

if the compound does not follow the rules, the least __________ will be in the center

electronegative