6.1.3 - Representing Molecules - Formulae

Cards (14)

types of formulae
Molecular
empirical
structural
skeletal
displayed
general
what does molecular formula show?
actual number of atoms of each element in a molecule
problem with molecular formula
doesn't show how atoms are joined together which is an issue due to isomers
what does structural formula show?
shows how atoms around a carbon are handed together in a molecule (carbon by carbon)
problem with structural formula
doesn't show all bonds
can be misleading as to what carbon functional group is bonded to
what does displayed formulae show?
shows all bonds & how atoms are arranged
so no confusion with molecules of the same formula
problem with displayed formula
2D
no bond angles shown so no indication to shape
different ways of arranging atoms can lead to confusion
what does skeletal formula show?
bonds between carbons shawn as lines with hydrogens removed I only functional groups shown
problem with skeletal formula
C & H symbols omitted so can be interpreted wrong
What does empirical formula show?
simplest whole number ratio of atoms in a compound
problem with empirical formula
doesn't indicate bonds, shape, angle or actual number of atoms
What's empirical formula used for?
ionic compounds
giant covalent structures
what does general formula show?
algebraic formula that can represent any compound in a homologous series
problem with general formulae
doesn't show how many atoms there are in a compound, shape or bonds