Atomic Structure Key Terms &
Questions
element - answera substance made of one kind of atom
atom - answerthe smallest particle of an element that cannot be broken down without
changing the properties of the element
nucleus - answerthe center of the atom, where the protons and neutrons are
located/can be found
electron cloud - answeran area of space surrounding the nucleus, where the electrons
can be found (hence the name)
neutron - answera neutrally charged particle found in the nucleus of an atom
electron - answera negatively charged particle found in the electron cloud
proton - answera positively charged particle found in the nucleus
atomic mass - answerthe average mass of all the protons and neutrons of the atom
mass number - answerthe number of protons and the number of neutrons (P+N=the
mass number)
compound - answertwo or more different elements that are bonded/fused together
molecule - answeranytime two or more atoms are bonded together
isotope - answerone of two or more atoms that have the same atomic number (number
of protons) but a different number of neutrons. Example: C-12 has 6 protons and 6
neutrons while C-14 has 6 protons and 8 neutrons.
A compound can be a molecule, but a molecule cannot be a compound...True or False -
answerTrue, all compounds are molecules, but not all molecules are compounds
Octet Rule - answerThe outermost energy level of any atom with 2 or more energy level
has the capacity of 8 electrons
Ion - answeran atom or molecule with an electric charge due to the loss (positive
charge) or gain (negative charge) of one or more electrons.
Questions
element - answera substance made of one kind of atom
atom - answerthe smallest particle of an element that cannot be broken down without
changing the properties of the element
nucleus - answerthe center of the atom, where the protons and neutrons are
located/can be found
electron cloud - answeran area of space surrounding the nucleus, where the electrons
can be found (hence the name)
neutron - answera neutrally charged particle found in the nucleus of an atom
electron - answera negatively charged particle found in the electron cloud
proton - answera positively charged particle found in the nucleus
atomic mass - answerthe average mass of all the protons and neutrons of the atom
mass number - answerthe number of protons and the number of neutrons (P+N=the
mass number)
compound - answertwo or more different elements that are bonded/fused together
molecule - answeranytime two or more atoms are bonded together
isotope - answerone of two or more atoms that have the same atomic number (number
of protons) but a different number of neutrons. Example: C-12 has 6 protons and 6
neutrons while C-14 has 6 protons and 8 neutrons.
A compound can be a molecule, but a molecule cannot be a compound...True or False -
answerTrue, all compounds are molecules, but not all molecules are compounds
Octet Rule - answerThe outermost energy level of any atom with 2 or more energy level
has the capacity of 8 electrons
Ion - answeran atom or molecule with an electric charge due to the loss (positive
charge) or gain (negative charge) of one or more electrons.
