Atoms and Elements

Describe the differences between elements, compounds and mixtures
1. ELements- Substance only made of one type of atom
2. Compounds- Substance made from more that one type of atom.
3. MIxture- Substance which has more than one type of element but not chemically bonded together
Describe the structure of an atom in terms of electrons and a nucleus containing protons and neutrons
1. An atom has a nucleus in middle containing protons and neutrons surrounded by shells containing electrons
Describe the build-up of electrons in ‘shells’ and understand the significance of the noble gas electronic structures and of valence electrons.
1. Each atom has outer shells containing electrons. The first outer shell of an atom is capable of containing only 2 electrons while the other can contain up to 8 electrons. Noble gases structure is the outer shell is filled and there is no more need for electrons for a complete outer shell.
State the relative charges and approximate relative masses of protons, neutrons and electrons
Define atomic (proton) number and mass (nucleon) number
1. Atomic number- number of proton.
2. Nucleon number- number of proton and neutron
Define isotopes
1. Isotopes are the atoms of the same element which have the same number of the proton but a different nucleon number.

Resource summary

	Created by Shravani Chingre about 6 years ago