Atom and periodic table

What was the first discovered part of the atom?

• Electron

• Proton

• Neutron

• quark

Democtrius' theory believed that all matter was made of tiny distinct elements.

• True

• False

What is the mass number of an element?

• the amount of protons

• the amount of electrons, protons, and neturons

• the amount of protons and neutrons

• the average mass of an element's isotopes.

What is the atomic mass?

• the average of the mass of the element's isotopes

• the average mass of electrons

• the average mass of the netrons and electrons

• the average mass of all atoms divided by 1800.

What makes an ion postive?

• The loss of an electron.

• The loss of a neutron.

• The loss of a proton.

• The loss of an electron's outer shell.

A negative ion loses an electron.

• True

• False

The Bohr's model of the atom shows...

• electrons moving in random, straight lines

• electrons moving in circular motions around a nucleus.

• electrons moving throughout the entire atom

What is an ion?

• An atom that gains or loses electrons

• Pieces of the atom that are atoms of the same element

• An atom that is the sum of the number of protons and neutrons in an element.

Aristotle believed that all matter is made of....

• Fire

• Air

• Water

• Earth

• All of these.

The isotope is the change in what number of the nucleus?

• Protons

• Neutrons

• Electrons

• Protons and Neutrons