Allotropes of carbon
Diamond, graphite and fullerenes are all allotropes of carbon. Diamond doesn't conduct electricity because it has no free electrons, but graphite does because it has delocalised electrons. Diamond is hard because it has many strong covalent bonds, meaning that it also has a high melting point. Graphite has layers of carbon atoms that are weakly held together, making it slippery.
Buckminster fullerene has the formula C60. Nanotubes are fullerenes that can be used to reinforce graphite in tennis rackets because they are very strong. They are also used as semiconductors in electrical circuits.
Nanotubes can also be used in the drug delivery system. This is because a molecule of the drug can be placed inside the nanotube cage, keeping the drug wrapped up until it reaches the site where it is needed.
Nanotubes have a massive surface area for their size, meaning that sticking a catalyst to the surface of a nanotube gives a huge area for the reactants to come into contact.
Hydrochloric acid is HCl Ammonia is NH3
Nitric acid is HNO3 Calcium carbonate is CaCO3
Sulphuric acid is H2SO4 Copper oxide is CuO
Potassium hydroxide is KOH Sodium carbonate is Na2CO3
Sodium hydroxide is NaOH Potassium chloride is KCl
Potassium sulphate is K2SO4 Sodium chloride is NaCl
Sodium sulphate is Na2SO4 Ammonium chloride is NH4Cl
Ammonium sulphate is (NH4)2SO4 Silver nitrate is AgNO3
Silver chloride is AgCl Barium chloride is BaCl2
Barium sulphate is BaSO4
alkalis and acids
An alkali is a soluble base. In a neutralisation reaction acid and a base produce water and salt.
Acids in a solution contain hydrogen ions. Alkalis in a solution contain hydroxide ions. In a neutralisation reaction H+ + OH- = H2O.
When carbonates neutralise acids water, salt and carbon dioxide is made.
Batch and Continuous Manufacturing
An advantage of batch manufacturing would be that it allows a range of products to be made. But it does mean that labour costs are high and time is wasted when the batch is switched so it isn't very efficient.
Continuous production is very efficient, works at full capacity and needs few workers. But it isn't flexible and will be very expensive to build.
Ammonia is made by continuous production, medicine is made by batch.
There are high costs in the production of drugs because it is more labour intensive and less automation is possible. The research and testing will also take along time, along with legislative demands the production company will have to adhere to. The raw materials may also be difficult to extract or even rare.
We can extract chemicals from plants by crushing the plants or boiling and then dissolving in a suitable solvent. Another way is chromatography.
Low temperature washes are useful because they save energy and the enzymes in biological washing powder work better.
Detergent molecules contain a hydrophilic head and a hydrophobic tail. The head forms intermolecular bonds with water and the tail forms bonds with the fat molecules in greasy dirt.
Most detergents are made from big organic molecules from crude oil. An acid group is added to one end of the molecule, which is then neutralised with a strong alkali to form a salt.
Dry Cleaning and Percentage Yield
Dry cleaning uses a solvent that isn't water because some stains don't dissolve in water.
The molecules form strong intermolecular bonds with the solute (stain) molecules, breaking the solute's intramolecular bonds.
Percentage yield is calculated by dividing the actual yield by the predicted yield and then multiplying that by 100.