History of Chemistry

2. Modern developed version of Crooke’s tube.
4. Used by Millikan by creating a known electrical charge on a drop of oil with known mass.
10. Concerned with transforming base elements into gold from the time of Aristotle until first half of 1700s.
12. The negatively charged particle of an atom located outside of the nucleus.
13. Established that the periodic table is arranged by atomic number not atomic mass.
14. Discovered oxygen by heating mercury(II) oxide in 1774.
18. Discovered that atoms contained smaller negative particles, electrons, using a Crooke’s or cathode ray tube.
21. Experimental setup used by Rutherford, shooting alpha particles through a gold foil.
24. Determined that an atom has a small dense positively charge center and is mostly empty space, 1911.
27. Discovered radioactivity.
29. Named oxygen. Established the law of conservation of mass.
30. Thought everything was made of four elements, earth, fire, water, and air.
31. Discovered the neutron.

1. (Geber) Arabic alchemist who developed many tools and procedures used by early chemists.
3. A particle made up of two protons and two neutrons, in other words, the necleus of a helium atom.
5. The positively charged particle of an atom located in the nucleus.
6. Established that science should be based on experimentation, observation, and measurements.
7. John Dalton’s model of the atom, small, indivisible, solid particles.
8. Thomson’s model of the atom. A cloud of positive charge with electrons embedded in it.
9. Rutherford’s model of the atom. A small, dense, positive core surrounded by electrons in orbits.
11. Vacuum tube used to investigate electrical discharges in gas.
15. Discovered polonium and radium, radium in 1898. The ONLY person to receive Nobel prizes in two sciences.
16. The number of protons in the nucleus of an atom.
17. Introduced the word, atomos, meaning uncuttable. Thought matter was made of atomos particles.
19. Established the law of multiple proportions. Proposed the atomic theory in 1804.
20. First modern chemist. Discovered the relationship between pressure and volume of gases – Boyle’s Law.
22. The small dense core of an atom where all of the positive charge exists.
23. Established the law of definite proportions.
25. Discovered and isolated the nobel gases. Discovered alpha particles.
26. Created the modern periodic table in 1869.
28. Determined the mass of an electron using the oil drop experiment.