Lucknow Public School Science Class X Revision Test PDF

Revision Test (SET-B) CLASS X SUBJECT: SCIENCE (086) TIME:- 2 HOURS M.M :- 50 General instruction for Question paper: - The question...

Revision Test (SET-B) CLASS X SUBJECT: SCIENCE (086) TIME:- 2 HOURS M.M :- 50 General instruction for Question paper: - The question paper consists of 24 questions in 5 sections. All questions are compulsory. However, an internal choice is provided in some questions. A student is expected to attempt only one of these questions. Section A consists of 12 objective-type questions carrying 1 mark each including multiple choice questions and assertion and reason. Section B consists of 4 very short questions carrying 2 marks each. Answers to these questions should be in the range of 30 to 50 marks. Section C consists of 4 short questions carrying 3 marks each. Answers to these questions should be in the range of 50 to 80 marks. Section D consists of 2 long questions carrying 5 marks each. Answers to these questions should be in the range of 80 to 120 marks Section E consists of 2 sources based/ Case-based units of assessment of 4 marks for each sub- part. SECTION A 1. You are asked to prepare hard water in your laboratory. Select a group from the following groups of salts, any salt of which you may dissolve in distilled water to obtain hard water. (a) NaCl; Na2SO4; KCl (b) NaCl; CaCl2; KCl (b) CaCl2; CaSO4; MgSO4 (d) Na2SO4; CaSO4; MgSO4 2. On adding a drop of given solution on a pH paper, a student noticed that the pH paper turned blue. From this observation, it was inferred that the given solution was (a) Dil CH3COOH (b) Dil.NaHCO3 (c) Dil. HCl (d) Conc.HCl 3. If the current I through a resistor is increased by 100% (assume that temperature remains unchanged), the increase in power dissipated will be (a) 100 % (b) 200 % (c) 300 % (d)400 % 4. In an electrical circuit two resistors of 2 Ω and 4 Ω respectively are connected in series to a 6 V battery. The heat dissipated by the 4 Ω resistor in 5 s will be (a) 5J (b) 10 J (c)20 J (d) 30 J 5. All metal carbonates and hydrogen carbonates react with acids gives a gas which (a) turns lime water milky. (b) is basic oxide. (c) gives pop sound (d) gives pungent smell 6. An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it? (a) 1A (b) 2 A (c) 4 A (d) 5 A 7. Which of the following acid cannot form acidic salt? (a) Nitric acid (b) Sulphuric acid (c) Carbonic acid (d) hydrochloric acid 8. Cylindrical conductor of length l and uniform area of cross-section A has resistance R. Another conductor of length 2l and resistance R of the same material has area of cross section (a) A/2 (b) 3A/2 (c) 2A (d) 3A 9. Identify the circuit in which the electrical components have been properly connected. (a) (i) (b) (ii) (c) (iii) (d) (iv) 10. Higher the hydronium ion concentration, (a) higher is the pH value (b) lower is the pH value (c) moderate is the pH value (d) pH value is the zero In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following: (a) Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion. (b) The Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion. (c) Assertion is true but the Reason is false. (d) Assertion is false but the Reason is true. 11. Assertion:- Sodium hydrogen carbonate is used as an ingredient in antacid. Reason:- NaHCO3 is a mild non-corrosive basic salt. 12. Assertion:- The coil of a heater is cut into two equal halves and only one of them is used into heater. The heater will now require half the time to produce the same amount of heat. Reason: The heat produced is directly proportional to square of current Section B 13. When zinc metal is treated with a dilute solution of a strong acid, a gas is evolved, which is utilised in the hydrogenation of oil. Name the gas evolved. Write the chemical equation of the reaction involved and also write a test to detect the gas formed. 14. Show how you would connect three resistors, each of resistance 9 Ω, so that the combination has a resistance of (i) 13.5 Ω, (ii) 6 Ω. 15. Give reasons: Use of a mild base like baking soda provides relief on the area stung by honeybee. 16. A student carries out an experiment and plots the I-V graph of three samples of nichrome wire with resistances R1 , R2 and R3 respectively (a)Write the resistances in decreasing order.  (b)Write slope of this graph. Section-C 17. A compound X of sodium is commonly used in kitchen for making crispy pakoras. It is also used for curing acidity in the stomach. Identify 'X'. What is its chemical formula? State the reaction that takes places when it is heated during cooking? 18. In the circuit diagram given below, the current flowing across 5 ohm resistor is 1 amp. Find the current flowing through the other two resistors. List the factors on which the resistance of a conductor in the shape of a wire depends. 19. A milkman adds a very small amount of baking soda to fresh milk. (a) Why does he shift the pH of the fresh milk from 6 to slightly alkaline? (b) Why does this milk take a long time to set as curd? 20. Ten bulbs are connected in a series circuit to a power supply line. Ten identical bulbs are connected in a Parallel circuit to an identical power supply line. a) Which circuit would have the highest voltage across each bulb? b) In which circuit would the bulbs be brighter? c) In which circuit, if one bulb blows out, all others will stop glowing d) Which circuit would have less current in it? Section -D 21. (I) How can three resistors of resistances 2 Ω, 3 Ω, and 6 Ω be connected to give a total resistance of (a) 4 Ω, (b) 1 Ω? (II) How will you infer with the help of an experiment that the same current flows through every part of the circuit containing three resistances in series connected to a battery? 22. A metal carbonate X on reacting with an acid gives a gas which when passed through a solution Y gives the carbonate back. On the other hand, a gas G that is obtained at anode during electrolysis of brine is passed on dry Y, it gives a compound Z, used for disinfecting drinking water. Identify X, Y, G, and Z. Write all the involved reactions. Section E Read the passage given below and answer the questions that follow: 23. Calcium hydroxide, which is a base, reacts with carbon dioxide to produce a salt and water. Since this is similar to the reaction between base and an acid we can conclude that non-metallic oxides are acidic in nature (i)What is the nature of Carbon dioxide? (ii)Give another reaction of non- metallic oxide and a base? (iii) Write the complete reaction between calcium hydroxide and carbon dioxide. (iv)What is the nature of non-metallic oxide? OR Give two examples of metallic oxide. 24. The obstruction offered by a conductor in the path of flow of current is called resistance. The SI unit of resistance is ohm Ω. It has been found that the resistance of a conductor depends on the temperature of the conductor. As the temperature increases the resistance also increases. But the resistance of alloys like mangnin, constantan and nichrome is almost unaffected by temperature. The resistance of a conductor also depends on the length of conductor and the area of cross-section of the conductor. More be the length, more will be the resistance, more be the area of cross-section, lesser will be the resistance. (i) Which property is desired in material being used for making electrical wires? (ii) What is the effect of Resistance on temperature? (iii) A wire of resistance 20Ω is cut into 5 equal pieces. The resistance of each part is.....Ohm (iv) Two wires of same material one of length L and area of cross-section A, other is of length 2L and area A/2. What will be the resistances of two wires? OR Calculate equivalent resistance when ‘n’ resistors of equal resistances (R) are connected in series?