Chapter-4. Structure of The Atom Science class 9 in english Medium CBSE Notes

Lesson - 4 

Q1.  Maximum, how many electrons are held in N orbit of an atom?

Ans: 32 electrons.

Q2.  What is the source of Alpha particles of Rutherford experiment?

Ans:  Double charged Helium particle.  

Q3.  Name the non-atomic particle which does not take part in atomic mass.

Ans: Electrons.

Q4.  Name the positive charged atomic particles which presence in nucleus.

Ans: Protons.  

Q5.  Copper has atomic number 29. Then what is its valency?

Ans: 1

Q6. Give the example of isobar?

Ans: Calcium, Argon

Q7.  Name the scientist who proposed that the atom is as chrismas cake.

Ans: J. Thomson.

Q8.  Name the scientist who discovered protons.

Ans: E Gold Steen.

Q9.  

Q10. Name the isotope of hydrogen which has 2 atomic mass number.

Ans: Deuterium

Q11.  Name the non-atomic particle which takes part in atomic mass and having no charge. 

Ans: Neutron

Q12. Name the isotope of element which is used in treatment of goiter. – Iodine

Q13.  Name the scientist who discovered the nucleus.  

Ans: Rutherford

Q14.   

Q15. Name the scientist who discovered the neutron.  

Ans: J. Chadwick

Q16. Name the isotopes of element which is used in atomic reacter as fuel.

Ans:  Uranium