Part 1

• Protons and neutrons make up the nucleus of an atom, whilst electrons orbit it

• Protons:    Relative mass-1.0         charge- 1+
  Neutrons: Relative mass-1.0         charge- 0
  Electrons: Relative mass-1/2000  charge- 1-

• The number of protons are equal to the number of electrons in an atom

   A                  <---- Mass number 

  X      <---- Element

  Z                    <----- Atomic number

• Mass number- The number of protons and neutrons in the nucleus of an atom
• Atomic number- the number of protons in the nucleus of an atom

• What makes up the nucleus of an atom?

• Fill in the missing blanks:

Protons:     Rel. Mass--                Charge--
Neutrons:   Rel. Mass--                Charge--
Electrons:  Rel. Mass--                Charge--

• What is the atomic number of an atom?

• Define the word mass number.

• Isotopes- Are atoms of the same element but with a different number of neutrons in the atoms nucleus

• isotopes of an element have different masses due to there being a different number of neutrons

• Isotopes of the same element react in the same way because reactions involve electrons not neutrons

• What is an isotope?

• Why does an atom of carbon-12 have a different mass to that of carbon-14?

• When experimenting with the two isotopes, we had discovered that both isotopes reacted in the same way, explain why this had happened?

• Ion- An ion is a positively charged or negatively charged atom or group of atoms

• Atoms can lose or gain electrons

• Ions are charged because they have a different number of electrons that protons in the atom

• Define the word Ion

• Why are ions charged?