chemical bonds Flashcards
what are elements that do not form a chemical bond under normal conditions?
helium(He),neon(Ne),argon(Ar)
why He,Ne and Ar not forming chemical bond?
because they have a stable electronic configuration with complete outer most shell
what is the purpose of making chemical bonds?
in order to have stable nobel gas configuration
what are chemical bonds?
the attractive forces or binding among the atoms or ions resulted bye the rearrangement of electrons in the valence shell for stabilizing the atoms of elements
what are 2 types of chemical bonds?
ionic and covalent
what is known as electrovalent bond?
ionic bond
what is ionic bond?
the bonds form due to strong electrostatic attractions between positive and negative ions produced by the exchange of electrons among atoms
how positive ions are formed?
when an atom remove electrons -cataions
how negative ions formed?
when an atom gain electrons-anions
what is an ion?
a group of atoms with electrical charges
what is covalent bond?
a bond formed by sharing electrons between pair of atoms
what is homoatomic molecules?
sharing of electrons between atoms of the same kind
what is heteroatomic molecules?
sharing of electrons between atoms of the different elements
what are known as electrons deficient molecule?
in covalent molecules the central atoms does not contains octets of electrons such molecules are known as electrons deficient molecules
what examples for electrons deficient molecule?
alluminium chloride and beryllium chloride
what are allotropes of carbon?
diamond and graphite
what are properties of carbon?
graphite layers of carbon atoms with formed by joining of one carbon atom with three other carbon atoms
the forces holding these are weak
have a ability of conducting electricity
graphite behaves as lubricants
what is hardest substannce in nature?
diamond
what are properties of diamond?
diamond is a 3d lattice in every carbon atom it forms four single bonds with another carbon atom
it cannot conduct elecricity
what is non polar covalent bond?
when an atoms with same or slightly different elecronegativity is joining by covalent bonds the bonding electrons between those two atoms are distributed symetrically it is known as non polar covalent bond
what is polar covalent bond?
when two atoms with unequal elecronegativity joining by a covalent bond it gets polarizes due to asymmetrical distribution of electrons
what is inercmolecular bonds?
attractive forces among molecules
what is known as intermolecular bond between water?
HYDROGEN bonds
why water has 100 degrees of boiling point?
because it is a intermolecular hydrogen bond
