The Evolution of Atomic Theory

Who was the first to propose that matter is made up of indivisible particles called 'atomos'?

• Democritus

• John Dalton

• JJ Thomson

• Ernest Rutherford

What did John Dalton propose about the composition of compounds?

• They consist of different types of atoms in whole number ratios.

• They are mostly empty space.

• They are made up of indivisible particles called 'atomos'.

• They contain electrons and protons.

What observation did Dalton's atomic theory explain about water?

• Water has a 1:8 ratio of hydrogen to oxygen by mass.

• Water has a 1:2 ratio of hydrogen to oxygen by mass.

• Water has a 1:1 ratio of hydrogen to oxygen by mass.

• Water is made up of indivisible particles.

What did JJ Thomson discover in his cathode ray experiment?

• The proton

• The electron

• The nucleus of the atom

• The neutron

What model did JJ Thomson propose for the atom?

• Plum pudding model

• Quantum model

• Planetary model

• Nuclear model

What was the surprising result of Rutherford's gold foil experiment?

• Most alpha particles were deflected.

• Most alpha particles passed through, but some scattered wildly.

• All alpha particles passed through the foil.

• All alpha particles were absorbed by the foil.

What did Rutherford conclude about the structure of the atom?

• Atoms have a dense nucleus with electrons far away.

• Atoms consist of electrons embedded in a positive sphere.

• Atoms are indivisible particles.

• Atoms are mostly solid.

What did Rutherford name the dense center of the atom?

• Proton

• Neutron

• Electron

• Nucleus

What percentage of the atom did Rutherford find to be empty space?

• 100%

• 50%

• 75%

• 99.95%

What impact did the acceptance of atomic theory have on the field of chemistry?

• It allowed chemistry to truly begin to flourish.

• It disproved the existence of atoms.

• It had no significant impact.

• It made chemistry more philosophical.