1) The atomic number of particle 3 is 5
Reason : The number of protons in an atom of an element is its atomic number. particle 3 has 5 protons. Thus, its atomic number is 5 .
2)The atom is called an ion when its numbers of electrons are not equal to protons . meaning, an atom can be attracted to another atom.
in this case, particle 1 has protons =4 which is not equal to the 2 number of electrons.
Therefore, particle 1 is an ion.
