Given below are the CBSE Structure of atoms class9 worksheet
(a) Fill in the blank's
(b) True and False
(c) Very short answer type
(d)Short answer type
(e)Long answer type
(f) Foundation level
Hope you like them and do not forget to like , social share and comment at the end of the page.
Fill in the blanks:
According to Maharishi Kanad, the tiniest to tiny particle of a pure substance is called _________.
An atom is the smallest unit of an element which takes part in a _________.
Mass of an electron is 1/1837 times less than the mass of one atom of__________.
The K-shell of any atom cannot have more than _________ electrons.
Isotopes are the atoms of ___________ element, having same atomic number but different mass number.
An atom of an element has 11 protons 11 electrons and 12 neutrons. The atomic mass of the atom is __________.
Almost all the mass of an atom is concentrated in a small region of space called the _______.
The subatomic particle not present in a hydrogen atom is________.
Cathode ray are a beam of fast moving ______ .
________and________ more or less complexly make up the mass of an atom.
The number of neutrons in the neutrons in the neutrons of an atom can be calculated by _______ the atomic number of _______its mass number.
The isotopes of an element do not differ in the number of _______ but do differ in the number of _______.
The type of radiations, which are not deflected in presence of electric or magnetic field are termed as rays.
The penetrating power of B-rays is_______ times more than a-rays.
Synthetic elements are those which are prepared by _________.
The control rods in a nuclear reactor are made up of _________.
_______ are stored in deep mines which are not in use.
When an elements emits B-particle, its mass number________.
Y-rays are________ radiations.
The difference between the actual isotopic mass and the sum of masses of protons, neutrons and electrons is called_________.
Who discovered the neutral particles present in an atom? Solution
What conclusion would you derive from the observation, that in Rutherford's scattering experiment, most of the alpha- particles passed through gold foil without any deflection? Solution
(a)Most of the space inside the atom is empty because most of the alpha-particles passed through the gold foil without getting deflected.
(b)Very few particles were deflected from their path, indicating that the positive charge of the atom occupies very little space.
Which shell is closest to the nucleus of an atom? Solution
Which energy level would accommodate the 17th electron? Question 7.
Select the isotopes from the following?
21/10A; 22/10B; 23/11C; 23/12D
Short Answer type
If an atom contains one electron and one proton, will it carry any charge or not? Question 9.
If K and L shells of an atom are full, then what would be the total number of electrons in the atom? Question 10.
Hydrogen exists in the three isotopic forms. Why are the isotopes of hydrogen chemically alike? Question 11.
Why alpha- particle scattering experiment was possible by using gold foil only and not by foil of any other metal? Question 12.
Write electronic configuration of the following elements and predict their valencies:
Long Answer type
Define the term valency? How is it different from valence electrons? Find the valency of oxygen and fluorine? Question 14.
What will be the composition of nucleus of the atom of an element with atomic number 19 and mass number 39? Also write its electronic configuration? Question 15.
Which of the two elements given below would be chemically more reactive:
'X' of atomic number 18 or element Z of atomic number 16? And why? Question 16.
An element has electronic configuration of 2,8,7:
(a)What is the atomic number of the element?
(b)What is the name of the elements?
(c)Which of the following elements have same number of valence electron? N(7), F(9), P(15) and Ar(18). Question 17.
State reasons for the following statements:
(a)Some elements possess fractional atomic mass.
(b)Isotopes of an element have similar chemical properties.
(c)Noble gases are inert. Question 18.
There are two elements A1326 and B1426. Find the number of sub-atomic particles in each of these elements. What is the relationship between the two?
Name the following processes:
(i)13AI27 + 2He4 -> 15P30 + 0n1 ->14Si30 + 1e0
(ii)5B10 + 2He4->7N13 + 0n1 ->6C13 + 1e0
(ii)5B10 + 2He4 -> 6C13 + 1e0 Question 20.
Complete the nuclear reaction expression:
(i)59/27Co (d, p)…………
(ii)27/13AI (a, n)………... Question 21.
Complete the following nuclear reaction equations by supplying the missing information:
(i)23/11Na +……. _____23/12Mg + 1/0n
(ii)27/13AI +…….______30/15P + 1/0n
This Structure of atoms class9 worksheet with answers is prepared keeping in mind the latest syllabus of CBSE . This has been designed in a way to improve the academic performance of the students. If you find mistakes , please do provide the feedback on the mail.
link to this page by copying the following text Also Read