Chemistry GCSE C7

C7.1 Alcohols, Carboxylic Acids and Esters.

C7.2 Energy Changes in Chemistry.

C7.3 Reversible Reactions and Equilibria.

C7.4 Analysis

C7.5 Green Chemistry 

HideShow resource information

Alcohols.

- Family of organic compounds.

- Contain the Hydroxyl group.

- Names end in 'OL.'

- First part of the name same as alkanes.

CH3OH = Methanol.

C2H5OH = Ethanol. 

- Alcohols have high boiling points relative for their weight.

- They can form Hydrogen bonds like water can.

- Alcohols are ORGANIC.

- Alcohols burn in air, they need slightly less oxygen as they already have some in them. 

- Alcohols react with sodium to form white crystaline alkoxides.

1 of 9

Alkanes.

- Family of Hydrocarbons.

- Made of only Carbon and Hydrogen. 

- Only have single bonds.

- All the names end in 'ANE.'

- The number of carbons in the molecule gives the first part of the name.

- Bonds STONG. 

- Not reactive. 

CH4 = Methane.

C2H6 = Ethane.

C3H8 = Propane.

C4H10 = Butane.

- When burnt always get gas.

2 of 9

Carboxylic Acids.

- Organic acids

- They are Proton donors. 

- The most common type of organic acid.

- Participate in Hydrogen Bonding.

- Carboxylic acids then to have higher boiling points than water, not only because of their increased surface area but to form stabilised dimers.

- Weak acids.

- Reactions convert Carboxylic acids into esters, amides, carboxylic salts, acid chlorides and alcohols. 

3 of 9

Esters.

- Chemical compounds.

- Creates when reacting an Oxoacid and a Hydroxyl compound. (Alcohol and Phenol.)

- Derived from Carboxylic acids or Alcohol. 

- Esters are formed by condensending and acid with an alcohol. 

- Esters with a low molecular weight are commonly used as fragrances and found in oils and pheromones.

- Low-ish melting point. 

4 of 9

Energy Transfer in Reactions.

- When a chemical reaction happens energy is usually transferred to or from the surroundings. 

- Exothermic Reaction = Energy is given out usually by heat. Eg- Burning fuels, Respiration, when water is added to Copper Sulphate. 

- Endothermic Reaction = Energy is taken in, often as heat, from surroundings. Eg- Photosynthesis, dissolving some Salts in Water, Thermal decompostion. 

5 of 9

Catalysts.

- Catalysts are substances that change the rate of reactions without being used up. 

- Most Catalysts speed up reactions and work by lowering the activation energy. 

- Catalysts that slow reactions down are called Inhibitors, they work by increasing the activation energy. 

- Enzymes are biological Catalysts. Enzymes work best at specific temperatures and stop working at higher temperatures. 

6 of 9

Bond Energies and Chromatography.

Bond Energies. 

- Measures the bond strength in a chemical bond. 

- Bond strength can be directly related to the bond length/ bond distance. 

Chromatography. 

- A set of laboratory techniques for the separation of mixtures.

- Preparative and Analyitical. 


7 of 9

Reversible Reactions.

- Most chemical reactions are considered irreversible.

- Reversible reactions occur when the backwards reaction takes place relatively easily under certain conditions. The product turns back into the reactants. 

- Biochemical reactions are normally reversible. 

FOR EXAMPLE.

- Red blood cells, oxygen binds to hameoglobin to create, oxyhaemoglobin. 

Dynamic equilibrium = can only take place in a closed system otherwise the products would escape. 

8 of 9

Ethanol.

- Ethanol is an alcohol.

- It is a flammable, clear liquid. 

- It's also used as fuel. 

- Ethanol is a straight-chain alcohol. 

Molecular formula = C2H50H

- Used as a solvent. 

9 of 9

Comments

Roisin

Very helpful! Contains all of the things I was most unsure about for my exam :)

Thanks x

Craig

not very detailed

Alex Head

TOENAILS

Alex Head

TOENAILS

zarah

not much detail

Grime

Not alot of detail

Zoe

lacking a bit of detail and info. 

Joe

awesome, thanks :D

Similar Chemistry resources:

See all Chemistry resources »See all resources »