Practice Paper – TERM II (2021 – 2022)
Class – IX
Science (086)
Time: 2 hours Maximum Marks: 40
General Instructions:
i) All questions are compulsory.
ii) The question paper has three sections and 15 questions. All questions are compulsory.
iii) Section–A has 7 questions of 2 marks each;
iv) Section–B has 6 questions of 3 marks each; and
v) Section–C has 2 case based questions of 4 marks each.
vi) Internal choices have been provided in some questions. A student has to attempt only one of the alternatives in such questions.
SECTION – A
1. The following data represents the distribution of electrons, protons and neutrons in atoms of three elements A, B and C. Understand the data carefully and answer the following questions:
| Element | Protons | Neutrons | Electrons |
| A | 9 | 10 | 9 |
| B | 16 | 16 | 16 |
| C | 12 | 12 | 12 |
(a) State the electronic configuration of element B.
(b) State valency of element A.
2. The number of atoms constituting a molecule is known as atomicity. Based on this fact answer the following:
(a) Name the elements whose atomicity is:
(i) Tetra atomic
(ii) Monatomic.
(b) State the number of atoms present in each of the following chemical species:
(i) CO32– (ii) HNO3
3.(a) J. Chadwick discovered a sub-atomic particle that has no charge and has mass nearly equal to that of a proton. Name the particle and give its location in the atom.
(b) If ‘K’ and ‘L’ shells of an atom are completely filled, then what would be:
(i) The total number of electrons in the atom and
(ii) Its valency?
4.(a) Pinky suffered from chickenpox last month. Her grandmother told her that now she would not suffer from this disease again. What is the reason for such a saying?
(b) How do children in many parts of India get immunized to Hepatitis ‘A’ by the time they are 5 years old?
5.We know that antibiotics are widely used in treatment of many diseases but it is observed that antibiotic such as Penicillin is not effective against common cold. Give reason.
OR
Given below is a list of certain diseases. Study the list carefully and answer the question below.
Elephantiasis, cough and cold, Tuberculosis, Diarrhoea.
(a) Which of these diseases will cause major ill-effects on general health?
(b) What are such diseases called?
6. A high-board diver of mass 50 kg is diving from a height of 30 m into a pool. Answer the following
questions on the basis of diagram. (Given g = 10 ms–2)
(a) What is the potential energy of diver at point A?
(b) What is the kinetic energy of diver at point D?
OR
(a) A horse of mass 210 kg and a dog of mass 25 kg are running with the same speed. Which of them two possesses more kinetic energy? Give reason to support your answer.
(b) If the speed of the body is halved, what is the change in its kinetic energy?
7. An artificial satellite is moving in a circular orbit of radius 42250 km. Calculate its speed if it takes 24
hours to revolve around the earth.
OR
Two solid objects of masses 1 kg and 2 kg are dropped from a helicopter at the same time. Which one
will reach the ground earlier? Give reason to support your answer.
SECTION – B
8.Two class students of class 9th, Aashi and Sheena, were asked to take 5.3 g of sodium carbonate and 6
g of ethanoic acid to make 2.2 g of carbon dioxide, 0.9 g of water and 8.2 g of sodium ethanoate. Aashi
followed the instructions but Sheena took the chemicals without measuring their amounts.
(a) Whose activity do you think will be in agreement with the law?
(b) Which law does this agreement show?
(c) State the law.
9.(a) What are isotopes? Why chemical properties of all the isotopes of an element are same?
(b) Name the isotopes used in the treatment of goitre and cancer.
OR
(a)What are the positively charged radiations produced in the discharge tube at low pressure and high
voltage called?
(b) State the nature of the constituents of canal rays. Who discovered canal rays?
10. Hydrogen has three isotopes. State the composition of their nuclei and write their mass numbers.
Also represent them in the form of symbols.
11.(a) Hydrogen and oxygen combine in the ratio of 1:8 by mass to form water. What mass of oxygen
gas would be required to react completely with 5 gm of hydrogen gas?
(b) An element ‘X’ shows variable valency of 4 and 6. Write the chemical formulae of its two oxides.
12. A and B are the two objects with same momentum but different masses. Object A is heavier than object B.
What is the ratio of their kinetic energies? Which one has a larger kinetic energy?
OR
A student of class IX of mass 50 kg runs up a staircase of 45 steps in 9s to reach his class. If the height of
each step of the staircase is 15 cm, find the power output of the student. (g = 10 m/s2).
13. Nisha always wonders about the phenomenon of motion of the moon around the earth.
(a) State the law which will help her to understand this phenomenon.
(b) Also mention two more examples which can be explained by the same law.
SECTION – C
14. Radha lives in an overcrowded and poorly ventilated house. When the person lives in an overcrowded area which is poorly ventilated house, the person may suffer from breathing and airborne related diseases. The person may suffer from respiratory infections and disorders.
(a) Which of the following diseases she may suffer from: high blood pressure/common cold?
(b) Why you should not allow mosquitoes to breed in your surroundings?
(c) Influenza or common cold, spreads faster and is difficult to control. Why?
OR
Chances of spreading of cholera are higher in a village. Give reason.
15. Energy is a capacity to do work. its unit is Joule (J), and it is a derived unit. It is named after the famous physicist James Prescott Joule. When one Newton of force is applied through one meter of distance, then it is said that one Joule of energy is expended. There are many forms of energy, such as mechanical, electrical, nuclear, solar, etc.
(a) What is meant by mechanical energy?
(b) State its two forms of energy.
(c) Give an example in which we observe a continuous change of one form of energy into another
and vice-versa. State the law of conservation of energy.
OR
Calculate the amount of work required to stop a car of 1000 kg moving with a speed of 72 km/h.