Atomic structure Flashcards
electrons have a relative mass of..
0
electrons have a relative charge of..
-1
electrons are located in..
the shells
neutrons have a relative mass of..
1
neutrons have a relative charge of..
0
neutrons are located in..
the nucleus
protons have a relative mass of..
1
protons have a relative charge of..
+1
protons are located in..
the nucleus
is the nucleus of an atom positive or negative?
positive
the nucleus contains..
protons and neutrons
protons are..
positive
neutrons are..
neutral
what is an atomic number of an element?
the number of protons in the nucleus of an atom
what is a mass number of an element?
the sum of the number of protons and neutrons in the nucleus of the atom
atoms of the same element can have different..
mass numbers due to a different numbers of neutrons
electrons orbit the..
nucleus in shells or energy levels
how many electrons does the first shell hold?
2
how many electrons does the rest of the shells hold?
8
what is the group number?
the number of outer shell electrons
what are horizontal rows called?
periods
what is an isotope?
they are atoms of the same element ie. have the same atomic number but different mass
isotopes have the same number of..
protons and electrons
isotopes have the different number of..
neutrons
