Paper 2 (7) Flashcards
What are Isomers?
Isomers are molecules that have the same molecular formula, but different structural formulas.
This means they are made of the same atoms, but the atoms are arranged differently.
Organic chemistry is about molecules that contain the element…
Carbon
Each atom of carbon can form ____ strong bonds, with the most common atoms to be bonded to being other ______ atoms or ________ atoms.
Each atom of carbon can form four strong bonds, with the most common atoms to be bonded to being other carbon atoms or hydrogen atoms.
Define Hydrocarbons
Any compound that is formed from carbon and hydrogen only.
Name the first four alkanes in the series
Methane - 1 Carbon atom bonded to 4 Hydrogen
Ethane - 2 Carbon 6 Hydrogens
Propane - 3 Carbon 8 Hydrogen
Butane - 4 Carbon 10 Hydrogen
What is the homologous series?
A homologous series is a group of organic compounds that have similar chemical properties, due to them having the same functional group.
What is the general formula for alkanes?
C(n)H(2n+2)
()=smaller
How many hydrogen atoms are there in an alkane with 5 carbon atoms?
12 hydrogen atoms
An alkane only has s_____ covalent bonds. There are no d_____ bonds or t_____ bonds.
single
double
triple
What is another way to describe hydrocarbons with only single bonds?
Saturated
As the chain length (number of carbon atoms) of alkanes increases, they become:
(viscous/ volatile/ flammable)
More viscous
Less volatile
Less flammable
Increasing the chain length - number of carbons - of alkanes leads to:
(boiling/ melting)
Higher boiling point
Higher melting point
What is the word equation for the complete combustion of a hydrocarbon?
hydrocarbon + oxygen ➔ carbon dioxide + water
C7H16 + ?O2 ➔ ?CO2 + _H2O
The above combustion reaction needs to be balanced. Start by balancing the number of H2O molecules so that the number of hydrogen atoms is equal on both sides of the equation.
8
C7H16 + ?O2 ➔ _CO2 + 8H2O
Next, balance the number of CO2 molecules by making sure there are an equal number of carbons on both sides of the equation.
7
C7H16 + ___O2 ➔ 7CO2 + 8H2O
Finish by balancing the number of O2 molecules, so that there are an equal number of oxygen atoms on both sides of the equation.
11
Is combustion an exothermic or endothermic reaction?
Exothermic
Oxidation is…
Reduction is…
Oxidation is… loss of electrons, gain of oxygen or loss of hydrogen. Reduction is… gain of electrons, loss of oxygen or gain or hydrogen.
During a combustion reaction, are carbon and hydrogen oxidised or reduced?
Carbon (C) becomes CO2, whilst hydrogen (H2) becomes H2O. Both have gained oxygen, so have been oxidised.
How to balance an odd number of oxygens:
Double everything, so the decimal becomes a whole number of molecules