Types of Formulae

Question 1

What are the seven types of formulae?

Answer 1

1) General formula

2) Empirical formula

3) Molecular formula

4) Displayed formula

5) Structural formula

6) Skeletal formulae

7) Three - dimensional structural formulae

Question 2

What is the general formula?

Answer 2

The algebraic formula used to describe any member of a family of compounds

Question 3

What are the general formulas for alkanes, alkenes and alcohols?

Answer 3

Alkane = CnH2n+2

Alkene = CnH2n

Alcohols = CnH2n+1OH

Question 4

What is the empirical formula?

Answer 4

The formula that gives the simplest ratio of atoms or each element in a compound

Question 5

What is the molecular formula?

Answer 5

Formula that gives the actual number of atoms of each element in one molecule

Question 5

What is the displayed formula?

Answer 5

The formula that shows all the bonds and atoms in a molecule

Question 6

What is the structural formula?

Answer 6

The formula that shows how the atoms are joined together in a molecule

Question 7

What is the skeletal formulae?

Answer 7

This formula uses lines to represent bonds
Each point representing a C atom
H atoms and bonds to H atoms are not usually shown
Other atoms are shown (O, N, F, Cl, Br, I, S)

Question 8

What is a three dimensional structural formulae?

Answer 8

This is an attempt to show the three dimensional structure of the molecule