Question

(a) What are isobars? Give one example. 

(b) Write two differences between isobars and isotopes. 

(c) Write any two uses of isotopes.

Answer 1

a. Isobars are the atoms of different elements having different atomic number but same mass number. Example- ₁₈Ar⁴⁰ , ₂₀Ca⁴⁰

b. Differences between isobar and isotopes

Isotopes	Isobars
They have a same atomic number but a different mass number.	They have a same mass number but a different atomic number.
They have the same number of protons/ electrons but neutrons number is different so they have similar chemical properties.	They have different chemical properties as they have different protons/electrons number.
Example: Isotopes of hydrogen: 1H1,1H2,1H3	Examples: Isobars: 18Ar40, 20Ca40

c. Two uses of isotopes are:

i. Radioactive isotopes are used as tracers in medicine to detect the presence of tumours, blood clots in the human body. 

ii. They are used in industry to detect leakage in underground oil, gas or water pipelines.