Atomic Theory and Atoms

What is an electron?

• Neutral particle in the nucleus of an atom

• Atomic particle with one positive charge (1+)

• Atomic particle with one negative charge (1-)

• Smallest piece of an element that still represents the element

Where is the electron cloud located?

• In the center of an atom

• Around the outside of the nucleus.

• Inside the nucleus

• In the space outside the atom

What does the atomic number of an element represent?

• The sum of protons and neutrons in an atom

• The average mass of an element's isotopes

• The number of protons in an atom of an element

• The number of neutrons in an atom

What is an isotope?

• An atom that has gained or lost electrons

• An atom with a different number of protons

• Any of two or more atoms of the same element that have different numbers of neutrons

• The smallest piece of an element that still represents the element

What is the mass number?

• The number of protons in an atom

• The average mass of an element's isotopes

• The number of neutrons in an atom

• The sum of protons and neutrons in an atom

What does the term "radioactive" describe?

• Elements that emit radiation when exposed to external force

• Elements that spontaneously emit radiation

• Elements that are stable and do not emit radiation

• Elements that absorb radiation

Tags

NGSS.HS-PS1-8

What is nuclear decay?

• The process of gaining or losing electrons

• The process that occurs when an unstable atomic nucleus changes into another more stable nucleus by emitting radiation

• The increase in the mass number of an atom

• The process of an atom splitting into two or more smaller atoms

Tags

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What does "spontaneous" mean?

• Occurring with external force or cause

• Occurring without external force or cause

• A process that requires energy input

• A process that is predictable and controlled

The smallest piece of an element that still represents that element is

• an electron

• a proton

• an atom

• a quark

What is an atomic particle with one negative charge?

• an electron

• a proton

• an atom

• a quark