Biological molecules
,Starter
• Explain the following terms. Draw diagrams to support:
• Element
• Atomic number
• Atomic mass
• Proton
• Neutron
• Electron
• Covalent bond
• Ionic bond
• Cation
• Anion
,Atoms
• All matter is made up of atoms
• Each atom is made of three types of particle:
– neutrons, with no charge
– protons, with a positive charge
– electrons with a negative charge
• The neutrons and protons form the nucleus
• The electrons orbit around the nucleus
• In an atom, the number of protons is the same as the
number of electrons (so no overall charge)
, How are electrons
arranged?
Electrons are not evenly spread but exist in layers called
shells. (The shells can also be called energy levels).
The arrangement of electrons in these shells is often
called the electron configuration.
1st shell
2nd shell
3rd shell
Note that this diagram is not drawn to scale – the atom is
mostly empty space. If the electrons are the size shown,
the nucleus would be too small to see.
,Starter
• Explain the following terms. Draw diagrams to support:
• Element
• Atomic number
• Atomic mass
• Proton
• Neutron
• Electron
• Covalent bond
• Ionic bond
• Cation
• Anion
,Atoms
• All matter is made up of atoms
• Each atom is made of three types of particle:
– neutrons, with no charge
– protons, with a positive charge
– electrons with a negative charge
• The neutrons and protons form the nucleus
• The electrons orbit around the nucleus
• In an atom, the number of protons is the same as the
number of electrons (so no overall charge)
, How are electrons
arranged?
Electrons are not evenly spread but exist in layers called
shells. (The shells can also be called energy levels).
The arrangement of electrons in these shells is often
called the electron configuration.
1st shell
2nd shell
3rd shell
Note that this diagram is not drawn to scale – the atom is
mostly empty space. If the electrons are the size shown,
the nucleus would be too small to see.