History of Atoms

Whose model suggested that negative particles were mixed in with positively charged material - like seeds in a watermelon?

• J.J. Thomson

• Ernest Rutherford

• Niels Bohr

• Albert Einstein

Who discovered that the atom had an small, dense, positively charged center?

• Ernest Rutherford

• J.J Thomson

• Robert Millikan

• John Dalton

Place the following atomic models in order, from earliest to latest:

A) Rutherford B) Thomson C) Dalton

• B, C, A

• C, A, B

• A, C, B

• C, B, A

Who named the positive center of the atom the "nucleus?"

• Democritus

• Dalton

• Thomson

• Rutherford

Which scientists believed an atom was indivisible? (Choose all correct responses.)

• Democritus

• Dalton

• Thomson

• Rutherford

Which scientist first suggested that atoms could join?

• Democritus

• Dalton

• Thomson

• Rutherford

Which scientist believed that elements differed from one another because their atoms had different mass?

• Democritus

• Dalton

• Thomson

• Rutherford

In the atomic model nicknamed the "plum pudding" model, what do the plums represent?

• the nucleus

• the atom

• the electrons

• the positive material

Which scientist proposed a new atomic model after discovering the electron in 1897?

• Dalton

• Thomson

• Rutherford

• Bohr

Aristotle thought that all substances were made of only four elements. What are those four elements?

• Fire, Water, Air, Earth

• Iron, Oxygen, Hydrogen, Nitrogen

• Wood, Fire, Earth, Metal

• Water, Earth, Wood, Metal

Answer explanation

Aristotle believed that all substances were composed of the four elements: Fire, Water, Air, and Earth. These elements were considered the building blocks of all matter.