Which of the following statements are incorrect about the structure of an atom ?
(i) The atom as a whole is neutral.
(ii) The atom is an indivisible particle.
(iii) The whole mass of an atom is concentrated in the nucleus.
(iv) All the atoms are stable in their basic state.
Correct option is :

Question

Which of the following statements are incorrect about the structure of an atom ? 
(i) The atom as a whole is neutral. 
(ii) The atom is an indivisible particle. 
(iii) The whole mass of an atom is concentrated in the nucleus. 
(iv) All the atoms are stable in their basic state. 
Correct option is :

Accepted Answer

Option 3 is the correct answer because statements (ii) and (iv) are incorrect about the structure of an atom. Let's examine each statement:

(ii) The atom is an indivisible particle: This statement is incorrect. The concept of the atom being indivisible was part of early atomic theory, but modern science has shown that atoms are composed of smaller subatomic particles: protons, neutrons, and electrons. These particles can be separated under certain conditions, such as in nuclear reactions.

(iv) All the atoms are stable in their basic state: This statement is also incorrect. Not all atoms are stable in their basic state. Many atoms, particularly those of radioactive elements, are unstable and can decay into other elements over time. Stability depends on the balance of forces within the nucleus and the arrangement of electrons.

Now, let's explain why the other options are incorrect:

1. (ii) and (iii): While statement (ii) is incorrect, statement (iii) is correct. The whole mass of an atom is indeed concentrated in the nucleus, as protons and neutrons, which are much heavier than electrons, reside in the nucleus.

2. (iii) and (iv): Statement (iii) is correct, as explained above. Therefore, this option is incorrect because it includes a correct statement as being incorrect.

4. (i) and (iv): Statement (i) is correct. An atom as a whole is neutral because the number of protons (positive charge) equals the number of electrons (negative charge), balancing the overall charge. Therefore, this option is incorrect because it includes a correct statement as being incorrect.

In conclusion, Option 3 is the correct choice because it accurately identifies the incorrect statements about the structure of an atom.