Grdae 8 Elements and the Periodic Table

Using evidence from many experiments, he inferred that atoms were like smooth, hard balls that could be broken into smaller pieces.

• John Dalton

• Democritus

• Ernest Rutherford

• Niels Bohr

A Danish Scientist suggested that electrons move in specific orbits around the nucleus of an atom.

• John Dalton

• Democritus

• Ernest Rutherford

• Niels Bohr

It is the number of protons in the nucleus of an atom.

• atomic mass

• chemical symbol

• atomic number

• elements

Which type of element conducts electricity?

• Metal

• Non-metal

• Metalloid

• Gas

Which type of element shines when light strikes it?

• Metal

• Non-metal

• Metalloid

• Halogen

What is the spontaneous emission of radiation by an unstable atomic nucleus called?

• Fission

• Fusion

• Radioactivity

• Ionization

Who observed that uranium exposure to sunlight could fog photographic film plates?

• Albert Einstein

• Marie Curie

• Henri Becquerel

• Niels Bohr

Where can nonmetals be found on the periodic table?

• Right side

• Left side

• Middle

• Bottom

The atomic nuclei of unstable isotopes release fast-moving particles and energy in a process called ______________.

• Nuclear decay

• Radioactive decay

• Atomic decay

• Elemental decay

What charge does an electron have?

• Negative
• Positive
• Neutral
• Contrated