Atomic Structure

Atomic Structure

1. Atom Drawing

   • Protons are positively charged. Their mass is 1
   • Electrons are negatively charged. They have no mass.
   • Neutrons have no charge. Their mass is 1

2. Isotopes

   • Isotopes are atoms of an element with a different number of neutrons.
   • When isotopes have to big nucleus, they are unstable. These are called radioisotopes. Radioisotopes can decay in three different ways: alpha decay, beta decay and gamma decay
     • Alpha decay
       • Alpha decay happens when there are too many protons in a nucleus. In this case, the element will emit radiation as positively charged particles: alpha particles.
     • Beta decay
       • Beta decay is caused when there are too many neutrons in a nucleus. In this case the element will emit radiation in the form of negatively charged particles called beta particles.
     • Gamma decay
       • Gamma decay happens when there is too much energy in the nucleus of an atom. In this case particles with no charge are emitted from the atom. These are called Gamma particles.

3. Periodic table.

   • Each horizontal line in the periodic table represents a period. Periods have numbers that represent the number of electron shells in an atom.
   • Each column in the periodic table represents a group. Each group represents the number of electrons in the outer shell.

4. Atom

   • Atomic mass
     • Protons + neutrons
   • Atomic Number
     • Protons+Electrons

5. Experiments.

   • When metals are tested with fire, produce a colour..