Atoms are made up of three parts.
Protons. Neutrons, and electrons.
Protons and neutrons are found in the nucleus, which is the central, of the atom.
Neutrons have no charge.
Protons are positively charged.
Electrons are negatively charged and zoom around the outside of the nucleus, in electron shells or energy levels.
Atomic mass and atomic number
On periodic tables we are given atomic numbers and atomic masses. The atomic number is situated at the top of the chemical. The atomic number is the number of protons in an atom. Electrons have the same number of protons as neutrons.
The atomic mass is situated at the bottem of the chemical on the periodic table. The atomic mass tells us the combined number of protons and neutrons their are in an atom.
Isotopes are atoms of the same element that have different masses, due to the different numbers of neutrons.
Before reacting, atoms are neutral because they have the same number of protons and electrons. When an atom gains or looses electrons to achieve stability it becomes an ion.
An ion is a charged particle.
Bonding is the attraction between atoms.
Their are two types of bonding: Ionic bonding and Covalent bonding.
Ionic bonding is when electrons are transferred from one atom to another. Usually from a metal to a non metal.
Properties of ionic bonds are hard, conduct heat and electricity, they have high melting points.
Covalent bonding is usually between two non metals and is when electrons are shared.
properties of covalent bonds have low melting points, insulate heat and electricity.
All living things (plants and animals) contain carbon compounds which are vital to their life. These compounds are referred to as organic compounds.
Organic compounds can be used as fuels , plastics, fibres, soaps, detergents, dyes, antibiotics, cosmetics, perfumes, paints, flavouring and more.
Organic compounds are made up of carbon, hydrogen and sometimes other elements such as oxygen or nitrogen.
This gives the number of each type of atom in the compound. e.g. C4H10
This gives the arrangments of atoms in a molecule, indicating how the atoms are bonded together.
The structual formular can also be written in a condensed form. e.g. butane: CH3CH2CH2CH3. This can also be simplified.
A formula which shows the general terms. This type of formula indicates what group it belongs to. i.e. Alkanes, alkenes or alcohols.
Series and groups
Groups that have the same functional group
A group of atoms that gives the compounds it's unique chemical and physical properties. e.g. Alkanes, alkenes and alcohols.
Hydrocarbons are organic compounds which contain only the elements carbon and hydrogen.
Alkanes and Alkenes
-Contain a single covalent bond.
-Have the general formula CnH2n+2
-Are saturated ( No more hydrogen atoms can be added to the molecules.
-Contain double c=c covalent bonds.
-Have the general formula CnH2n
-Are unsaturated ( more hydrocarbon atoms can be added to the molecules)
Polymers are very large molecules made up of small repeating units
Alkenes can react together to make a type of polymer called 'additional polymers'. (plastics).
An individual alkene is known as a monomer, they add and join together to form a polymer.
When an alkene molecule reacts, one of the C=C bonds breaks and joins with a neighbouring molecule to form a long chain. Many molecules join together and this is represented by putting the monomer in bracets and adding the letter 'n' which can be represented by any number.
Two commen polymers
Polyethene is made up of ethene.
There are two types of polyethene.
High Density Polyethene (HDPE)
This is produced at low pressure and long linear chains are formed.
Low Density Polyethene (LDPE)
This is produced under high pressure
General formula: CnH2n+20.
insoluble=Can't be dissolved in a liquid.
soluble = Can be dissolved in a liquid.
The -OH group makes alcohol soluble in water and the carbon chain allows them to be soluble in oils.
Uses of alcohols are they can be used as solvents, fuels, ethanol beverages..
Methanol and Ethanol
-Is a colourless liquid.
-It will mix well with both oils and water which mean it is a good solvent.
-Highly toxic, can kill.
Ethanol is made by fermentation. Brewing or alcoholic fermentation is the conversion of sugar glucose (C6H12O6) into carbon dioxide gas (CO2) and ethanol (CH3CH2OH).
This process is carried out by yeast cells using a range of enzymes. This speeds up the process.
This overall process of fermentation is to convert glucose sugar to alcohol and carbon dioxide gas.
In other words burning to find the final products.