I have listed out the questions of chapter Atomic structure of CBSE 9th Science, from previous year question papers. Mentioned the year and marks beside the questions. Will upload the answers in next post.
Questions from Previous year Question papers
1.
a) If an element ‘M’ has mass number 27 and atomic number 13, how many protons and neutrons does its atom contain? What valency will be shown by M?
b)Write the electronic configuration of an atom with atomic number 6 (3marks) (2013 SA II)
2.
a)Write the symbol and the name of the element having 14 protons (1)
b) Complete the table(3)
| Element | Atomic No. | Mass No. | Proton | Neutron |
| Cl | 17 | – | – | 18 |
| Si | – | 28 | – | – |
| F | – | – | 9 | 10 |
b)Give the drawback of Rutherford model (1) (2012 SAII)
OR
3.(2012 SAII)
a. The average atomic mass of a sample of an element X is 16.2 u. What are the percentage of isotope 16X8 and 18X8 in the sample.(3
b. On the basis of Thomson’s model of an atom, explain how the atom is neutral as a whole? (2)
4.(2014 SA II)
An atom contains3 protons, 3electrons and 4 neutrons. Find its atomic number, mass number and valency ?(3)
5. (2016 -17SAII)
a) Write two main postulates of Bohr’s model of an atom.(2)
b) From the symbol 40Ca20 write electronic configuration and valence electrons(1)
6.(2016 -17SAII)
a) State major drawbacks of Rutherford’s model of an atom(1)
b)Draw sketch of Aluminum showing distribution of electrons in various shells.(1)
c)Calculate average mass of chlorine, on the basis of this data, atomic number 17, Mass number 35, 37 and their ration 3:1.(1)
7.Write the names of three elementary particles which constitute an atom. (1) (2015-16 SAII)
8.What will be the composition of nucleus of the atom of an element with atomic number 19 and mass number 39? Also write electronic configuration(3) (2015-16 SAII)
9.Define a) Atomic number b) Mass number (1) (2015-16 SAII)
10.There are two elements , A2613 and B2614.Find the number of sub atomic particles in each of these elements. What is the relationship between the two.(3) (2015-16 SAII)
11.Define the term valency. How is it different from valence electrons? Find the valency of Oxygen and Fluorine (3) (2015-16 SAII)
12. (2015-16 SAII)
a) i) Name scientist who discovered neutrons (3)
ii) State the charge and mass of a neutron
iii) Where is neutron located in an atom?
b) Helium atom has an atomic mass of 4u and two protons in its nucleus. How many neutrons does it have.
13.An electron attributes negative charge , protons attribute positive charge .An atom has both. But why there is no charge? (1) (2015-16 SAII)
14.(2015-16 SAII)
a) Why does Helium has zero valency?
b)Name the scientist and his experiment to prove that nucleus of an atom is positively charged.(3) .
15. a)Define the term isobar with one example.(1)(2014 SAII)
16.(2014-15 SAII)
a) Name the subatomic particles of an atom(3)
b)An atom of an element has 5 electrons in L Shell
(i) What is the atomic number of the element?
(ii)State its valency
(iii)Identify the element and write its name.
17.Name the fundamental particle which is not present in hydrogen atom(1) (2013-14 SAII)
18. (2013-14 SAII)
Give reasons for the following(5)
a)40Ar18 and 40 Ca20 are called isobars
b)He and Ne have zero valency
c)An atom is neutral
d)Nucleus is positively charged
d)Isotopes have similar chemical properties.
19.Write atomic symbol and Latin name of Iron (1) (2016-17 SAII)
