Atoms and Atomic Theory

The first scientist to suggest that atoms contain smaller particles was________________

• Democritus

• Dalton

• JJ Thomson

• Rutherford

• Bohr

In an atom, the number of protons is greater than the number of electrons.

• True

• False

Tags

NGSS.MS-PS1-1

Positively charged particles in an atom are called

(a)  

Bohr proposed that electrons in an atom are found in specific _____________

• regions

• clouds

• energy levels

JJ Thomson proved that cathode rays were beam of __________

• Protons
• Neutrons

• Electrons

The first person to suggest the idea of atoms was ___________.

• Bohr

• Democritus

• Dalton

• JJ Thomson

Negatively charged particles in an atom are called (a)  

_____________found that an atom is made mostly of empty space

• Bohr

• Rutherford

• Dalton

• JJ Thomson

The center, or core, of an atom is called the (a)  

Surrounding the core of an atom is a cloud of very small particles called (a)  

Tags

NGSS.MS-PS1-1