GCSE P4 TEST REVISION

GCSE P4 TEST REVISION

1. Protons have a mass of 1 and and charge of 1+

   • The proton is found in the nucleus.

2. Neutrons have a mass of 1 and a charge of 0.

   • The neutron is found in the nucleus.

3. Electrons have a mass of 1/2000 ( 0) and a charge of 1-

   • The electron orbits the nucleus.

4. Mass number= number of protons +neutrons (biggest number in the element)

5. Atomic number = number of protons (smallest number in the element)

6. The number of electrons is always the same as the number of protons (smallest number)

7. The typical radius of an atom is 1 times 10 to the power of 10 minus 10m

8. An isotope are 2 atoms of the same element with the same number of protons but a different anumber of neutrons.

9. If an atoms loses or gains an electron it becomes an ion.