EL1

Simple Model of the Atom

Atoms can be considered to consist of 3 sub-atomic particles

• Proton, Mr 1, Charge of +1

• Neutron, Mr 1, Neutral

• Electron, Mr \(\frac{1}{2000}\), Charge of -1

• Most of the atom is empty space

Nuclear Symbols

• Atomic Number, Z

  • Number of protons

  • Lower number

  • Equal to charge on Nucleus

• Mass Number, A

  • Number of protons and neutrons

  • Highest number

Isotopes

• Atoms of same element with different mass numbers

• Different number of neutrons

Relative Atomic Mass

• Average of relative Isotopic Masses relative to Carbon-12

• Taking abundance into account

• Mass Spectrometry used to find it

Mass Spectrometry

• Measures atomic/molecular mass of different particles, and relative abundances

• Ionised to cations

• Separated by mass to charge ratios

Nuclear Fusion

In a nuclear fusion reaction, two light atomic nuclei fuse together to form a single, heavier nuclei, releasing huge amounts of energy in the process of doing so

• Impossible at normal temperature and pressure

• Positive nuclei repel too strongly

• Possible in stars, repulsion overcome

\[{^{1}_{1}H}+{^{2}_{1}H}={^{3}_{2}He}+\gamma\]