chem scientist of atom

Question 1

Democritus

Answer 1

• 5th century BC
• cut stones in half until they could no longer be divided
• thought that everything was made of tiny indivisible particles but had no evidence

Question 2

Dalton

Answer 2

• 1803
• studied measurements and observations of many chemical reactions
• theory stated that all matter is made of indivisible atoms

Question 3

Thompson

Answer 3

• 1897
• discovered the electron with the cathode ray tube experiment
• proposed a positively-charged sphere with negatively- charged electrons embedded throughout

Question 4

Rutherford

Answer 4

• 1911
• discovered the nucleus with the gold foil experiment
• proposed that the atom had a positively charged nucleus with electrons moving around outside

Question 5

Bohr

Answer 5

• 1913
• studied the line spectra of atoms
• proposed that electrons orbit the nucleus in specific energy levels

Question 6

Schrodinger

Answer 6

• 1926
• created a mathematical equation to describe the location of an electron
• proposed that orbitals are regions of space with a high probability of finding an electron