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.Two electronic configurations for an element are shown below.
(a) Identify the electronic configuration for magnesium atom and magnesium ion from the following:
(b) How does the electronic configuration of magnesium atom differ from bivalent magnesium ion?
2.Given below are the molecular formulae of some compounds.
(a) Calculate the molar mass of these:
(i) Ethyne (C2H2).
(ii) Phosphorus molecule (P4) (Atomic mass of C = 12 u, H = 1 u and P = 31 u).
(b) What is the name given to the amount of substance containing 6.022 × 1023 particles (atoms,
molecules or ions) of a substance?
3. An element ‘Z’ forms the following compound when it reacts with hydrogen, chlorine, oxygen and
phosphorus. ZH3, ZCl3, Z2O3and ZP
(a) What is the valency of element Z?
(b) Element ‘Z’ is metal or non-metal?
4.Nisha and Neera were studying the health and diseases. They had a dispute on whether signs of the
disease is more important or symptoms.
(a) What according to you are more important – signs or symptoms?
(b) Justify your answer.
5. According to a newspaper report, some areas in Delhi received grey coloured water in their taps. It was reportedly due to mixing of contents at some points due to leakage in sewage and water supply pipes.
(a) Which kind of diseases are likely to spread due to such problems and why?
(b) Name any two diseases that can thus be spread.
OR
Which disease is more harmful: acute or chronic? Why are we advised to take bland and nourishing food when we are sick?
6.The given figure shows mass of a body and weight of the same body.
(a) It is observed that mass of the body remains constant whereas its weight keeps changing. Why?
(b) While explaining force, teacher wrote on the board ‘g’ and ‘G’ showing different values. Reema is
confused between the two. Help her to understand the differences between ‘g’ and ‘G’.
OR
Account for the following:
(a) On moon, man feels lighter than earth.
(b) Mass is scalar while weight is a vector quantity.
7. A moving vehicle of mass ‘m’ is moving with velocity ‘v’. It has momentum of ‘p’ and kinetic energy
K.E. Derive a relation between its kinetic energy K.E. and momentum ‘p’ with mass ‘m’ and velocity ‘v’.
OR
Account for the following:
(a) When displacement is in a direction opposite to the direction of force applied, what is the type
of work done?
(b) Seema tried to push a heavy block of 100 kg for 200 s but could not move it. Find work done by
Seema at the end of 200 s.
SECTION – B
8. (a) Find the mass of 10 moles of sodium sulphite (Na2SO3). (Na = 23 u; S = 32 u; O = 16 u)
(b) (i) Calculate the number of molecules in 8 gm of oxygen gas. (ii) Convert 22 gm of CO2 into moles.
9. (a) List any two Bohr-Bury rules for distribution of electrons in different shells.
(b) Draw the atomic structure of an atom with atomic number 11.
OR
The electronic configuration of an element ‘X’ is 2, 8, 2.
(a) What will be the number of electrons present in the atom of element ‘X’?
(b) Element ‘X’ will be a metal or a non-metal? Give reason to support your answer.
10. (a) What do the following symbols / formulae stand for:
(i) 2O (ii) O2 (iii) O3 (iv) H2O
(b) Give the chemical formula of the following compounds:
(i) Potassium carbonate (ii) Calcium chloride
11.(a) An atom of an element has three electrons in its 3rd orbit, which is the outermost shell. Write:
(i) The electronic configuration (ii) Atomic number
(b) (i) number of protons (ii) valency
12. What is the magnitude of the gravitational force between the earth and a 1 kg object on its surface?
(Given, ME = 6 × 1024 kg and RE = 6.4 × 106 m)
OR
The gravitational force between two objects is 100 N. How should the distance between these object be
changed so that the force between them becomes 50 N?
13. (a) It is possible that a body is displaced and yet its work done is zero? If yes, write an example.
(b) A boy is moving on a straight road against a frictional force of 5 N. After travelling a distance of 1.5
km he forgot the correct path at a round of radius 100 m. However, he moves on the circular path for
11⁄2 cycle and then he moves forward upto 2 km. Calculate the work done by him.
SECTION – C
14. Although Sonia has been suffering from cold and cough she decided to go in a party, where she had
a great party with all her friends. She enjoyed and shared all the food with them. However, only one of
them actually suffered from cold and cough.
(a) What type of disease is cough and cold?
(b) Which term is used to refer the system of an individual that fights off infection carrying
microbes?
(c) State any two preventive measures to control cough and cold.
OR
What is the causative agent of cough and cold: Bacteria/virus? Name the term used for such agent that
produces diseases.
15. Kinetic energy is the energy required due to motion, while potential energy is the energy acquired
due to position. These are interconvertible.
(a) State the law of conservation of energy.
(b) When an arrow is shot from a bow, from where will the arrow acquire its kinetic energy?
(c) When a body falls freely towards the earth, then, what happens to its total energy? Explain.
OR
A body is falling from height ‘h’, when it reaches the height of h/2, what will be its potential and kinetic
energy? Will it possess only kinetic energy or half potential and half kinetic energy? Justify your answer