Chemistry Chapter 3

An explanation supported by many experiments, still subject to new data and can be modified

• Theory
• Scientific gues

• a thought

• nothing at all

The atomic number of an element is

• The mass of the element

• The number of neutrons in each atom of the element

• The number of protons in each atom of the element

• 1 mole of the element

A visual, verbal, and/or mathematical explanation of data collected from many expirements.

• Model
• Example

• Explanation

• A hope

Democritus believed that matter was made up of

• Atoms

• Particles

• Air

• Nothing

Aristotle said that ______ cannot exist.

• empty space

• atoms

• air

• full space

Why were Democritus's ideas not science?

• They were not supported by experiment.

• They were partially incorrect.

• They went against ideas of more influential philosophers.

• They were ahead of their time.

What can you conclude from the deflection of a cathode ray in a magnetic field?

• The ray must be composed of charged particles.

• The ray must be composed of iron.

• The ray must have a positive charge.

• The ray must need to travel in a vacuum.

Which subatomic particle was discovered by researchers working with cathode-ray tubes?

• Electron

• Proton

• Neutron

• Quark

Aristotle's ideas gained greater acceptance because ____.

• He backed up his ideas with experimental evidence.

• He tested his ideas.

• He was one of the most influential philosophers of his time.

• Empty space cannot exist.

Which of the following parts of John Dalton's atomic theory were not correct?

• Atoms are indivisible.

• Matter is composed of atoms.

• Atoms of one element differ from atoms of another.

• Atoms combine to form compounds.