History of the atom timeline worksheet

What is the name of John Dalton’s theory?

• Atomic Theory
• Chemical Bonding Theory
• Molecular Theory
• Kinetic Theory

What are elements made of?

• Elements themselves
• Compounds
• Molecules
• Atoms

An atom of hydrogen and an atom of carbon are __________________________.

• different chemical elements
• the same chemical element
• different isotopes
• different compounds

What are compounds made of?

• Compounds are made of two or more elements.
• Compounds are made of atoms from the same element.
• Compounds are made of molecules only.
• Compounds are made of single elements.

The ratio of atoms in HCl is:

• 1:3

• 2:1

• 1:1

The ratio of atoms in H₂O is:

• 1:3

• 2:1

• 1:1

What did J.J. Thompson discover?

• The neutron
• The electron
• The proton
• The nucleus

By convention, the charge of an electron is negative,______, while that of a proton is positive, +e. Charged particles whose charges have the same sign repel one another, and particles whose charges have different signs attract.

• +e

• -f

• =e

• −e

What are cathode rays made of?

• Protons
• Electrons

• Neutrons
• Photons

Why do electrons move from the negative end of the tube to the positive end?

• Electrons are repelled by the positive charge.
• Electrons move randomly without any direction.
• Electrons do not move at all in the tube.
• Electrons move from the negative end to the positive end due to the attraction to the positive charge.