Question

Assertion: Atoms are not electrically neutral.
Reason: Number of protons and electrons are different.
A. Both assertion and reason are true and the reason is a correct explanation of the assertion.
B. Both assertion and reason are true but reason is not a correct explanation of the assertion.
C. Assertion is true but reason is false.
D. Both the assertion and reason are false.
E. Assertion is false but reason is true.

Answer 1

Hint: Atom is defined as the smallest unit of a matter. An atom consists of electrons, protons and neutrons. Atoms are very small, typically around $100$ picometers. Solid, liquid and gases are composed of atoms that may be ionized or neutral

Complete answer:
Atom is the smallest unit of any matter that combines to form an element. An atom consists of nucleus and electrons, that are bound to nucleus. Nucleus consists of protons and neutrons. Electrons have negative charge, protons have positive charge and neutrons have no charge, that means, they are neutral. The number of electrons will determine whether an atom is electrically neutral or charged. Atoms are electrically neutral because they have an equal number of protons and electrons, and as we know that the protons and electrons contain opposite types of charge, hence their negatively charged electrons are completely balanced with their positively charged protons.
Hence, we can say that both the assertion and reason are false.
So, the correct answer is “Option D”.

Additional Information:
-An atom consists of electrons, protons and neutrons, in which neutrons and protons have approximately same mass, that is, $1.67\times {{10}^{-24}}g$ and electrons have mass equal to $9.10\times {{10}^{-31}}kg$ . Therefore, an electron is considered nearly massless in comparison with the neutron and proton.
-Electrons are present in shells that surround the nucleus of the atom. Nucleus consists of protons and neutrons, and hence the nucleus is positively charged.

Note:
-Matter is composed of atoms.
-Atoms are electrically neutral because they contain the same number of electrons and protons, which contain opposite types of charges.
-The number of protons present in the nucleus is called as the atomic number of the element and the total number of protons and neutrons is called as the mass number of that element.