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LC Chemistry
LC Chemistry

Chemical Bonding Notes

  • Compound: two or more different elements combined together chemically
  • Octet Rule: when bonding occurs, atoms tend to reach an electron arrangement with 8 electrons in the outermost energy level
  • Ion: a charged atom or group of atoms
  • Ionic bonding: the force of attraction between oppositely charged ions in a compound. Formed by the complete transfer of an electron from one atom to another
  • molecule: a group of atoms joined together, the smallest particle of an element with can exist independently
  • valency: the number of atoms of hydrogen (or any monovalent element) with which each atom of the element combines
  • Transition... (More)
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LC Chemistry

All Chemistry Definitions to Learn for Leaving Certificate - Higher Level

The Atom

  • Dalton’s Atomic Theory: All matter is made up of indivisible atoms which cannot be created or destroyed.
  • William Crookes discovered the Electron. Cathode ray tube.
  • JJ Thomson determined that electrons were negative. Found E/M ratio.
  • Robert Millikan’s Oil drop experiment discovered size of electron’s charge.
  • Plum Pudding Model: Solid positive sphere with electrons embedded.
  • Rutherford discovered the Nucleus. Fired alpha particles at gold foil. Proton.
  • Chadwick discovered the neutron by firing alpha particles at beryllium.
  • Energy level is the fixed energy value that an electron in an atom may have.
  • Heisenberg’s Uncertainty Principle states that it is... (More)
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LC Chemistry

Chemistry Experiment: Flame Tests (Li, Na, K, Ba, Sr & Cu)

To carry out flame tests with salts of lithium, sodium, potassium, barium, strontium and copper.

Procedure

  1. Light a bunsen burner and adjust it to obtain a blue flame.
  2. Dip the wooden splint in water and add one of the salt to it so it sticks on.
  3. Place the wooden splint over the flame to observe the colour of the flame.
  4. After the salt has finished burning put the flame out and take note of the colour.
  5. Repeat this for all the different salts.

Results

  • LithiumDeep red
  • SodiumYellow
  • PotassiumLilac
  • BariumGreen
  • StrontiumRed... (More)
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LC Chemistry

Organic Chemistry – Fuels & Heats of Reaction

Organic chemistry is the chemistry of carbon containing compounds.

A hydrocarbon is a substance that contains only carbon and hydrogen.

There are three main hydrocarbons on the course – alkanes, alkenes and alkynes.

A homologous series is a series of compounds:

  • of similar chemical type.
  • that show gradual change in their physical properties.
  • all are prepared in a similar way.
  • have a common general formula
  • differ one from the next by a
  • group.

The Alkanes

The first homologous series we deal with is calles the alkanes (The ending tells us the chemical family).

Structural Isomers

Structural isomers... (More)