4.1.2: Organic Compounds + Formulae

Question 1

what is alkenes general formula?

Answer 1

CnH2n

Question 2

what is alcohols general formula?

Answer 2

CnH2n+1OH

Question 3

what is a displayed formula?

Answer 3

shows the relative positions of all the atoms in the molecule and the bonds between them

Question 4

what is a structural formula?

Answer 4

gives minimum detail for detail of arrangements in a molecule e.g butane
CH3(CH2)2CH3

Question 5

what is a general formula?

Answer 5

the simplest algebraic formula for a homologous series

Question 6

what is an empirical formula?

Answer 6

shows the smallest whole number ration of atoms of elements in a compound

Question 7

how do you work out empirical formula?

Answer 7

find Ar, calculate moles - mass/Ar
divide by smallest number, change ratio to whole numbers

Question 8

what is the molecular formula?

Answer 8

the number and types of atoms in a compound

Question 9

how do you calculate the molecular formula?

Answer 9

calculate empirical formula, divide Mr by empirical formula mass, multiply each atom in empirical formula by number calculated in step 2