Unit 2 Vocabulary List A Practice

the sum of the number of protons and neutrons in the nucleus of an atom

• atomic number

• energy levels

• mass number

• isotope number

the possible energies that electrons in an atom can have

• energy levels

• electron cloud

• orbitals

• isotopes

the arrangement of electrons in the orbitals of an atom

• electron cloud

• electron configuration

• atomic theory

• ground state

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

all matter is made up of individual particles called atoms, which cannot be divided

• excited state

• electron cloud

• isotopes

• atomic theory

Tags

NGSS.MS-PS1-1

a visual model of the most likely locations for the electrons in an atom

• orbital

• electron cloud

• nucleus

• energy level

a state in which all the electrons in an atom have the lowest possible energies

• excited state

• atomic theory

• ground state

• electron configuration

a negatively charged subatomic particle that is found in the space outside the nucleus of an atom

• proton

• neutron

• electron

• isotope

Tags

NGSS.MS-PS2-5

a neutral subatomic particle that is found in the nucleus of an atom

• proton

• neutron

• electron

• isotope

a positively charged subatomic particle that is found in the nucleus of an atom

• proton

• neutron

• electron

• isotope

the state in which one or more of the electrons in an atom have moved to an orbital with higher energy

• electron configuration

• nucleus

• ground state

• excited state