Correct Answer - Option 1 :
54X
27
Concept-:
- An atom is made up of subatomic particles of negatively charged electrons, positively charged protons, and neutral neutrons.
- The number of protons and electrons in an atom is the same so as to make the atom neutral as a whole
- The total number of electrons (or protons) in a neutral atom is called its atomic number, denoted by Z.
- The total number of protons and neutrons in the nucleus of an atom is known as its Mass Number and is denoted by A.
- The number of neutrons is calculated by the difference in M-A.
- An element is represented as writing the symbol and writing the atomic number as subscript and atomic mass as superscript like.
- When an element gains one electron, the number of electrons exceeds the number of protons and hence it gains a negative charge.
- The negative charge is equal to the number of electrons gained.
- When an element loses electrons, it gains a positive charge and the amount of positive charge is equal to the number of loss in protons.
- The negatively charged species is called the anion is written as X- whereas the positively charged species is called the cation.
Calculation:
The species and their number of electrons, protons, and neutrons are:
Species |
Electrons |
Protons |
Neutrons |
54X27
|
27 |
27 |
54 - 27 = 27 |
55X+27
|
27 - 1 = 26 |
27 |
55 - 27 = 28 |
54X26
|
26 |
26 |
54 - 26 = 28 |
55X+28
|
28 - 1 = 27 |
28 |
55 - 28 = 27 |
- From the above table, we see that 54X27 has 27 neutrons, 27 protons, and 27 electrons.
Hence, the species having the same number of electrons, proton, and neutrons is 54X27.
-
Electrons lie outside of the nucleus in circular paths called orbits or shells whereas the protons lie inside of the nucleus.
- The number of electrons in an atom can be altered by the gain or loss of electrons but not protons.
- The removal of electrons from the outermost shells of electrons can be done by providing them with an energy called ionization energy.