Simple Model Of The Atom
- Every atom has a central, positively charged nucleus that is very small but massive
- The nucleus is made up of positive protons and neutral neutrons
- Electrons revolve around the nucleus in allowed orbits
- A vast amount of empty space within an atom
Electron
- Mass: 9.1094 x 10-31 kg
- Charge: -1.602 x 10-19 C
Nucleus diameter: around 10-15 m
Atomic diameter: around 10-10 m
Proton:
- Mass: 1836 x mass of electron, 1.6726 x 10-27kg
- Charge +1.602 x 10-19 C
Neutron:
- Mass: 1839 x mass of electron, 1.6749 x 10-27 kg
- Charge: Neutral
Proton number (atomic number), Z, gives the number of protons in a nucleus.
The nucleon number (mass number), A, gives the total number of nucleons(protons + neutrons) in the nucleus.
A = Z + N, where N is number of neutrons in the nucleus.
Isotopes are atoms that have the same number of protons but different number of neutrons.
- Same number of electrons
- Same chemical properties
