More of a History Lesson!

Todays class was very different from the rest of the year!
So far we've pretty much done math and then more math that gets super confusing! But now we are starting the history part of chemistry 11.
Today we looked at the Atomic theory and Philosophers ideas of Atoms back in the day!

• The first idea from Greek philosophers of atoms was that they were the smallest particles of matter.
• Aristotle believed that matter was made from different combinations of earth, air, fire and water
• Alchemists tried turning to turn common elements to gold
• These ideas lasted for 2000 years
• In 300BC Democritus; greek philosopher, thought atoms were invisible particles

Next we looked at a few philosophers and talked about their theories on matter!

Lavoisier

1. Lavoisier

• He created the first version of the law of conservation of mass, and the law of definite proportions
• he was the first to recognize and name Oxygen(1778) and Hydrogen(1785)

2.Proust

• He experimentally proved Lavoisier law



Dalton

• he stated that ratio of elements will stay the same before and after.

3. Dalton

• idea that atoms are solid, indestructible spheres
• atoms provide for different elements, based on the law of conservative mass

5 main points of Dalton's Atomic Theory

1. elements are made of tiny particles
2. all atoms of a given elements are identical
3. all atoms of a given element are different from those of any other element
4. Atoms of one element ca combine with atoms of other elements to from chemical compounds
5. atoms can not be created nor destroyed, only changed

4. J.J. Thomson (1850)

planetary model

• blueberry muffin model
• discovered existence of electrons

5. Rutherford (1908)

• discovered the nucleus and that electrons orbit the nucleus
• created planetary model
• claimed atoms were mostly empty space

 Atomic Theory IV

Niels Bohr

6. Niels Bohr (1885-1962)

• observations, electrons surrounding the nucleus had specific "energy levels" or "shells"
• Pictured hydrogen atoms having energy "levels"
• and that they could jump to higher levels
• release light when it comes back down

The Modern Atom

•  atom is the smallest particle of an element
•  all atoms are made up of 3 subatomic particlles

1. electrons
2. protons
3. neutrons

Lastly we got assigned a Timeline to do for April 20
we have to research 12 scientists and construct a time line

1. Aristotle
2. Henri Becquerel
3. Niels Bohr
4. James Chadwick
5. Marie & Pierre Curie
6. John Dalton
7. Democritus
8. Robert Millikan
9. Ernest Rutherford
10. J.J. Thomson
11. Antoine Lavoisier
12. Henry Mosely

A few of these scientists were discussed today in class as shown above!