Atomic Structure

The structure of the atom The Ancient Greeks used to believe that everything was made up of very small particles. I did some experiments in 1808 that proved this and called these particles ATOMS: Dalton ELECTRON – negative, mass nearly nothing PROTON – positive, same mass as neutron (“1”) NEUTRON – neutral, same mass as proton (“1”)

Mass and atomic number 4 He 2 Particle Relative Mass Relative Charge Proton 1 Neutron Electron -1 MASS NUMBER = number of protons + number of neutrons He 2 4 SYMBOL PROTON NUMBER = number of protons (obviously)

The Atom Electron Nucleus Shell or Orbit

The Atom Hydrogen Proton Electron Hydrogen has one proton, one electron and NO neutrons

The Atom Helium Proton Electron Neutron Helium has two electrons, two protons and two neutrons

The Atom Helium Proton Electron Neutron Helium has two electrons, two protons and two neutrons

The Atom Lithium Electrons Protons Neutrons

The Atom Beryllium Electrons Protons Neutrons Beryllium has four electrons, four protons and five neutrons.

The Atom Boron Electrons Protons Neutrons Boron has five electrons, five protons and six neutrons.

The Atom Carbon Electrons Protons Neutrons Carbon has six electrons, six protons and six neutrons.

The Atom Nitrogen Electrons Protons Neutrons Nitrogen has seven electrons, seven protons and seven neutrons.

The Atom Oxygen Electrons Protons Neutrons Oxygen has eight electrons, eight protons and eight neutrons.

The Atom Fluorine Electrons Protons Neutrons Fluorine has nine electrons, nine protons and ten neutrons.

The Atom Neon Electrons Protons Neutrons Neon has ten electrons, ten protons and ten neutrons.

The Atom Sodium Electrons Protons Neutrons Sodium has eleven electrons, eleven protons and twelve neutrons.

HELIUM ATOM + - + - Shell proton neutron electron What do these particles consist of?

How many protons, neutrons and electrons? 1 11 16 H B O 1 5 8 23 35 238 Na Cl U 11 17 92

Ionic and Sub Atomic Particles Ion = atom or group of atoms who gain or lose electron(s) CATION +1 23 lose 1 electron in its outer shell Na Number of proton = 11 Number of electron = 11 – 1 = 10 11 Number of neutron = 23 – 11 = 12 +2 24 lose 2 electrons in its outer shell Mg Number of proton = 12 12 Number of electron = 12 – 2 = 10 Number of neutron = 24 – 12 = 12

Ionic and Sub Atomic Particles ANION -2 16 gain 2 electron in its outer shell O Number of proton = 8 Number of electron = 8 + 2 = 10 8 Number of neutron = 16 – 8 = 8 -1 35 gain 1 electrons in its outer shell Cl Number of proton = 17 17 Number of electron = 17 + 1 = 18 Number of neutron = 35 – 17 = 18

ISOTOPES 1 2 3 H H H 1 1 1 Hydrogen Deuterium Tritium p = 1 n = 0 Isotopes = same number of protons different number of neutrons = same AN; different MN

ISOBARS 3 3 H He 1 2 p = 1 n = 2 e = 1 p = 2 n = 1 e = 2 Isobars = same mass number (p + n)

ISOTONES 3 4 H He 1 2 p = 1 n = 2 e = 1 p = 2 n = 2 e = 2 Isotones = same number of neutrons

Determine these following pairs of atoms as isotope, isobar or isotone! 39 39 1. 4. 19 20 K Cl F Ne and and 19 17 9 10 isobar isotone 2. 30 31 5. 10 11 P S B B and and 15 16 5 5 isotone isotope 3. 15 17 6. 105 106 N O Ag Cd and and 7 8 47 48 isotone isotone

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