Question

State the meaning of the following terms:
i) Protons
ii) Neutrons
iii) Electrons
iv) Atomic number of an atom
v) Mass number of an atom​

Answer 1

Answer:

i) A stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron.

ii) A subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.

iii) A stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.

iv) It is the no. of protons in the nucleus of an atom

v) Mass number of an element is the sum total of the numbers of protons and neutrons contained in the nucleus of an atom of an element.

Relation between Mass number and Atomic number:

Mass number (A) = Atomic number (Z) + Number of neutron (n) : A = Z+n An element X having mass number A and atomic number Z

Answer 2

Answer:

i) Protons : Proton, stable subatomic particle that has a positive charge equal in magnitude to a unit of electron charge and a rest mass of 1.67262 × 10−27 kg, which is 1,836 times the mass of an electron.

ii) Neutrons: are the particles in an atom that have a neutral charge. They aren't positive like protons. They aren't negative like electrons. ... So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge.

iii) An electron is a negatively charged subatomic particle. It can be either free (not attached to any atom), or bound to the nucleus of an atom. Electrons in atoms exist in spherical shells of various radii, representing energy levels.

iv) The atomic number or proton number of a chemical element is the number of protons found in the nucleus of every atom of that element. The atomic number uniquely identifies a chemical element. It is identical to the charge number of the nucleus.

v) Mass number of an atom

Together, the number of protons and the number of neutrons determine an element's mass number: mass number = protons + neutrons. If you want to calculate how many neutrons an atom has, you can simply subtract the number of protons, or atomic number, from the mass number.