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. Study the given picture.
(a) Which atomic model does the given picture describe?
(b) What does the model inform about the structure of atom?
2. Teacher explained the concept of bivalent cations as follows: These are the cations having valency 2.
Now, help Nidhi to write the answers for the following:
(a) Molecular formulae of
(i) Hydroxide of calcium.
(ii) Sulphate of potassium.
(b)Two examples of bivalent cations.
3 (a) Both Helium and Beryllium have two electrons in the valence shells. Helium is a noble gas whereas
Beryllium is a metal. Justify.
(b) Hydrogen exists in three isotopic forms. Why are the isotopes of hydrogen chemically alike?
4. For the prevention of infectious diseases, some public health programmes of childhood immunization
are conducted in the country.?
(a) Name two such diseases which are covered under this programme.
(b) Name a disease which has been eradicated from the world. State the principle behind its
eradication.
5. A person is suffering from chest pain, breathlessness, loss of body weight, persistent cough
and produces blood-stained sputum?
(a) Name the disease he must be suffering from.
(b) If the bacteria causing this disease enter the patient’s body through nose, which organ of the
body will they attack most likely?
OR
We know that diseases that can be spread from one person to another are called communicable
diseases.
(a) How do these diseases spread?
(b) Which of these is a communicable disease – Cancer/tuberculosis?
6. A ball is thrown vertically upwards with a velocity of 49 m/s. Calculate:
(a) The maximum height to which it reaches.
(b) Calculate the total energy when ball reaches in maximum height.
OR
A 60 kg mountain climber is in the final stage of the ascent of 1000 m high Pikes peak.
(a) What is the change in gravitational potential energy as the climber gains the last 100 m of
altitude?
(b) How much work is done to climb the mountain shown in figure?
7. A bar of metal has a mass 200 g and a certain weight. Mass remains the same when weighed at
equator but weight decreases.
(a) Why does the change in weight occur at equator?
(b) State any one difference between mass and weight of an object.
OR
Reena is confused in the terms, gravitation and gravity.
(a) Help her to find the difference between gravitation and gravity.
(b) Weightlessness is a state when an object does not weigh anything. When does an object
show weightlessness?
SECTION – B
8. If 18 g of pure water is electrolysed, 2 g of hydrogen and 16 g of oxygen is obtained.
(a) Which law of chemical combination is illustrated by this statement?
(b) State the law of constant proportion. Illustrate with the help of an example.
(c) Which postulate of Dalton’s atomic theory is the result of law of conservation of mass?
9.(a) Define valency. What conclusions can be drawn about the reactivity of an atom from its valency?
(b) Why does an atom of Argon have zero valency? Explain using the electronic configuration of Argon.
OR
Calculate the number of electrons, protons and neutrons in an atom of an element with atomic number
20 and mass number 40.
10. Define formula unit mass. Calculate formula unit mass of NaCl. (Atomic mass of Na = 23 u, Cl=35.5u.)
11. There are two elements 26A13 and 26B14
(a) Find the number of sub-atomic particles in each of these elements.
(b) What is the relationship between the two?
12. What is power? Calculate the power of an electric motor that can lift 800 kg of water to store in a
tank at a height of 1500 cm in 20 s. (g = 10 m/s2)
OR
(a) A person holds a bundle of hay over his head for 30 minutes and gets tired. Give reason. Has he done
some work or not? Justify your answer.
(b) Define 1 kWh.
13 (a) Identify the physical quantity denoted by ‘g’. State its SI unit.
(b) Derive an expression for acceleration due to gravity in terms of mass M of earth and its radius R.
SECTION – C
14.Doctors always say that for good health personal hygiene, balanced diet and immunization are
necessary.
(a) State the role that personal hygiene plays to keep away diseases.
(b) What is the role of balanced diet in maintaining good health?
(c) Write any two precautions that you can take in your school to reduce the incidence of infectious
diseases?
OR
Explain how individual health depends on social and mental well-being.
15. A stone of 0.5 kg is thrown with velocity 3 m/s upwards from a point A, as shown in the figure. After
reaching the highest point B at 9 m it comes down. (Given, g = 10 m/s2)
(a) Explain the transformation of energy from A to B and B to A.
(b) State the difference between kinetic energy and potential energy.
(c) Calculate the type of energy possessed by the stone at point A and B of its journey.
OR
A body of mass 20 kg is dropped from a height of 100 m. Find its K.E. and P.E. after
(a) 1st second (b) 2nd second
