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What is Isobars ?

What is Isobars :

Isobars are the atoms of different elements whose mass number is the same but atomic number differs. For example, the mass number of calcium and argon, both, is 40 but their atomic number are 18 and 20 respectively. Similarly, mass number of Carbon-14 and Nitrogen-14, is 14 hence they are Isobars. In ths type of atoms the sum of protons and neutron is the same but in both the number of protons is different.

The basic particles of atom are electron, proton and neutron.
The negatively charged particles in the atom are electrons.
The numeric value of the charge on electron and proton is the same but their sign is opposite.
James Chadwick discovered neutrons.
There are 6.022×10²³ particles in one mole. This is known as the Avogadro number.
The NTP volume of 1 mole of a gas is 22.4 litres.
The formula to determine the maximum number of electrons in a shell is 2n² .
When the atomic number is the same but mass number is different they are known as Isotopes.
Isobars are elements having different atomic number and the same mass number.
There are three isotopes of hydrogen, Protium, Deutirium and Tritium.

1. The Plum Pudding Model of atom was given by:
(a) Neil Bohr
(b) Thomson
(c) Ernest Rutherford
(d) Goldstein

Answer⇒ { B}

2. The discoverer of neutron was :
(a) C.V. Raman
(b) Rutherford
(c) J.J. Thomson
(d) James Chadwick

Answer ⇒ { D}

3. The size of atom is :
(a) 10^-6 cm
(b) 10^-15 cm
(c) 10^-2 cm
(d) 10^-8 cm

Answer ⇒ {D }

4. The number of neutrons in the Deutirium Isotope of hydrogen is /are :
(a) one
(b) Two
(c) Three
(d) Not even one

Answer ⇒ {A }