(55) protons
(56) nucleus
(57) chemical
(58) atomic
(59) protons and neutrons
(60) neutrons
(61) electrons
(62) equal
(63) ion
The atomic number is the number of
(55) ______ (positively charged particles)
(56) in the ______. It is unique for each
(57) element.
(58) The ______ mass number of the element
(59) ______the number of ______and ______
(60) (neutral, no charge) in the nucleus.
(61) ______ (negatively charged particles) are also in the atom. Atoms usually have (62) an ______number of ______and electrons. When the ______of protons and (63) electrons is not equal the element is called an ______.
1 answer
1 answer