10 Class General Science 1st Term Exam 2023-24: N. K. Bagrodia

10 CBSE General Science Exam: First Term Exam 2023-24: N.K. Bagrodia Public School, Rohini

School Name:	N. K. Bagrodia Public School, Sector 9, Rohini, New Delhi 110085 India
Class:	10th Standard (CBSE)
Subject:	Science
Time Duration:	03 Hours
Maximum Marks:	80
Date:	~ September 2023

General Instructions:

• The question paper comprises of five sections A, B, C, D and E. There are 39 questions in the question paper. All the questions are compulsory.
• Section A – Question number 1 to 20 are of 1 mark each. These questions contain multiple choice questions, assertion reason questions, and very short answer questions. Answers to these should be given in one word or one sentence.
• Section B – Question number 21 to 26 are short answer questions, carrying 2 marks each. Answers to these questions should be in the range of 30 to 50 words.
• Section C – Question number 27 to 33 are short answer questions carrying three marks each. Answers to these questions should be in the range of 50 to 80 words.
• Section D – Question number 34 to 36 are long answer questions, carrying 5 marks each. Answers to these questions should be in th6 range of 80 to 120 words.
• Section E – Question number 37 to 39 are case based questions. Each question consists of 3 parts (a), (b) and (c). Part (a) and (b) are compulsory but there is choice for part (c).
• There is no overall choice. However, internal choices have been provided in some questions. A student has to attempt only one of the alternatives in each questions.
• Wherever necessary, neat and properly labelled diagrams should be drawn.

Section A

Question: 01. Which of the following oxide(s) is / are soluble in water to form alkalies?

(i) Na₂O (ii) SO₂ (iii) K₂O (iv) NO₂

1. (i) and (iii)
2. (i) only
3. (ii) and (iv)
4. (iii) only

Question: 02. Sodium reacts with water to form sodium hydroxide and hydrogen gas. The balanced equation which represents the above reaction is

1. Na_(s) + 2 H₂O₍₁₎ —-> 2NaOH_(aq) + 2H_2(g)
2. 2Na_(s) + 2H₂O₍₁₎ —-> 2Na0H_(aq) + H_2(g)
3. 2Na_(s) + 2H₂O₍₁₎ —-> NaOH_(aq) + 2H_2(g)
4. 2Na_(s) + H₂O₍₁₎ —-> 2Na0H_(aq) + 2H_2(g)

Question: 03. C₆ H₁₂ O_{6 (aq)} + 6O_{2 (aq)} —> 6CO_2 (aq) + 6H₂O₍₁₎
The above reaction is a / an

1. displacement reaction
2. endothermic reaction
3. exothermic reaction
4. neutralisation reaction

Question: 04. Select from the following statements which is true for Bases

1. Bases are bitter and turn blue litmus red
2. Bases have a pH less than 7
3. Bases are sour and changed red litmus to blue
4. Bases turn pink when a drop of phenolphthalein is added to them

Question: 05.  Study the following table and choose the correct option:

Question: 06. Which one of the following reactions is categorized as thermal decomposition reaction?

1. 2H₂ O ₍₁₎ —-> 2H2 _(g) + O_2 (g)
2. 2AgBr _(s) —> 2 Ag _(s) + Br_{2 (g)}
3. 2AgCl _(s) —-> 2Ag _(s) + Cl_2 (g)
4. CaCO_3 (s) —-> CaO _(s) + CO_2 (g)

Question: 07. Consider the pH value of the following acidic samples:

which solution will contain maximum H⁺ ions.

1. S. No. 1
2. S. No. 2
3. S. No. 3
4. S. No. 4

Question: 8. Define peristalsis and give its significance.
OR
Define emulsification.

Question: 9. Given below is a diagrammatic representation of a process taking place in the human body

In which of these regions / organs could it be occurring?
(i) Lungs (ii) Heart (iii) Brain

1. Only (i)
2. Only (ii)
3. Only (i) and (ii)
4. In all – (i), (ii) and (iii)

Question: 10. Sometimes after vigorous exercise you feel cramps in muscles due to

1. non conversion of glucose to pyruvate
2. conversion of glucose to pyruvate
3. conversion of pyruvate to ethanol
4. conversion of pyruvate to lactic acid

Question: 11. Observe the diagram of human digestive system.

Match the labelling referred in column I and correlate with the function in column II:

1. (i)-(A), (ii)-(B), (iii)-(C), (iv)-(D)
2. (i)-(B), (ii)-(C), (iii)-(D), (iv)-(A)
3. (i)-(B), (ii)-(D), (iii)-(C), (iv)-(A)
4. (i)-(D), (ii)-(A), (iii)-(B), (iv)-(C)

Question: 12. In flowering plants, the growth of pollen tube towards the ovule is an example of _________.

Question: 13. The image distance from the eye lens in the normal eye when we increase the distance of an object from the eye

1. Increases
2. Decreases
3. remains unchanged
4. depends on the size of the eyeball

Question: 14. The image of a candle flame formed by a lens is obtained on a screen placed on the other side of the lens. According to new Cartesian sign convention, if the image is three times the size of the flame, then the lens is

1. concave and magnification is +3
2. concave and magnification is -3
3. convex and magnification is +3
4. convex and magnification is -3

Question: 15. Which of the following statements about the transmission of nerve impulse is incorrect?

1. Nerve impulse travels from dendritic end towards axonal end.
2. At the dendritic end electrical impulses bring about the release of some chemicals which generate an electrical impulse at the axonal end of another neuron.
3. The chemicals released from the axonal end of one neuron cross the synapse and generate a similar electrical impulse in a dendrite of another neuron.
4. A neuron transmits electrical impulses not only to another neuron but also to muscle and gland
   cells.

Question: 16. Rahul sprayed a chemical ‘X’ on a plant with rosette habit. After few days, he found the internodal distances to have increased suddenly. The chemical ‘X’ might be:

1. Ethylene
2. Auxin
3. Abscisic acid
4. Gibberellin

For question numbers 17 to 20 two statements are given – one labelled Assertion(A) and the other labelled Reason(R). Select the correct answer to these questions from the options (a), (b), (c) and (d) as given below:

• (a) Both (A) and (R) are true and (R) is correct explanation of the assertion.
• (b) Both (A) and (R) are true but (R) is not the correct explanation of the assertion.
• (c) (A) is true but (R) is false.
• (d) (A) is false but (R) is true.

Question: 17.  Assertion (A): Sodium hydrogen carbonate is used as an ingredient in antacids.

Reason (R): NaHCO3 is mild non-corrosive basic salt.

Question: 18. Assertion (A): Muscles move based on the direction made by the brain.

Reason(R): Muscles are made of special proteins that change both their shape and arrangement of cell based on nervous impulses.

Question: 19. Assertion: A concave lens of very short focal length causes higher divergence than one with longer focal length.

Reason: The power of a lens is directly proportional to its focal length.

Question: 20. Assertion (A): Abscisic acid is called stress hormone.

Reason(R): Abscisic acid is responsible for wilting of leaves during drought conditions.

Section – B

Question: 21. A student took a small amount of copper oxide in a conical flack and added dilute hydrochloric and to it with constant stirring. He observed a change in colour of the solution.

1. Write the name of the compound formed and its colour.
2. Write a balanced chemical equation for the reaction involved.

Question: 22. What is geotropism? Draw a labelled diagram of a potted plant showing positive geotropism and positive phototropism.
OR
Explain with the help of a diagram why does a plant bend towards light during growth.

Q23. Give reason:

1. Alveoli is densely covered with blood vessels.
2. Rings of cartilage is present in the air passage.

OR

With the help of a flow chart, explain the breakdown of glucose into carbon dioxide and water. Also specify the site of occurrence for each step involved.

Question: 24.

• What do you mean by absolute refractive index?
• The absolute refractive indices of benzene and kerosene are 1.50 and 1.44 respectively. What is the refractive index of benzene with respect to kerosene?

Question: 25. With the help of a ray diagram, explain that the colours of white light splitted by a glass prism can be recombined to get white light by another identical glass prism.
OR
Draw a well labelled diagram to show the formation of rainbow.

Question: 26. Different parts of the brain are associated with specific functions. Name the part of human brain which perform the following functions:

1. Sensational feeling full
2. Salivation
3. Riding a bicycle th
4. Respiration

Section – C

Question: 27. List the important products of the chlor — alkali process, write one important use of each.

Question: 28. Explain why calcium metal after reacting with water starts floating on its surface. Write the chemical equation for the reaction. Name one more metal that starts floating after sometime when immersed in water.
OR
Question: 28.

1. Give one example each of the metals that are good conductors and poor conductors of heat respectively.
2. Name one metal and one non-metal that exists in liquid state at room temperature. Also name two metals having melting point less than 310K (37°C).

Question: 29.

1. List two factors on which the amount of urine produced depend.
2. Draw a well labelled diagram of human excretory system.

Question: 30. If you happen to move in bright sunlight from a dark room, what would be your response? With the help of a reflex arc explain the reflex action involved.

Question: 31. Give reasons:

• Red colour is selected for danger signals
• The sky appears dark in space
• The position of an object, when seen through the hot air, fluctuates or wavers

Question: 32. A convex lens of focal length 25 cm and a concave lens of focal length 10 cm are placed in close contact with each other. Calculate the lens power of this combination.

Question: 33.

• State the two laws of refraction.
• Give reason:
• A convex mirror is preferred as a rear- view mirror in vehicles.
• When a ray of light travelling in air enters obliquely into water, it bends towards normal.

Section – D

Question: 34.

(a) Why is aluminium oxide considered as amphoteric oxide. Explain using reactions. (2+3) ‘C,

(b) Of the three metals X, Y and Z. X reacts with cold water, Y with hot water and Z with steam only. Identify X, Y and Z and write the reactions involved.

OR

(a) Compare the reactivities of the following metals with cold and hot water :

1. Sodium
2. Calcium
3. Magnesium

(b) Complete and balance the following chemical equations.

1. Cu + Ag NO3 —>
2. Fe + H2O Steam —>

Question: 35.

(a) List three cellular components of blood. State one function of each component.

(b) Explain the process of double circulation with the help of a flow chart.

OR

Question: 35.

(a) What do the following transport?

1. Xylem
2. Phloem
3. Pulmonary vein
4. Vena cava
5. Pulmonary artery
6. Aorta

(b) Give reason:

1. Presence of valves in the blood vessels.
2. The wall of left ventricle is thicker than the wall of right ventricle.

Question: 36. A lens produces a magnification of – 0.5. Is this a converging or diverging lens? If the focal length of the lens is 6 cm, draw a ray diagram showing the image formation in this case. A o, state one use of the same lens.

OR

(a) A security mirror used in a big showroom has radius of curvature 5 m. If a customer is standing at a distance of 20 m from the cash counter, find the position, nature and size of the image formed in the security mirror.

(b) List four characteristics of image formed by a concave lens for an object placed at a finite distance infront of the lens.

Section – E

Question: 37.  Salts are formed by reaction of acids and bases. Strong acids reacts with strong bases to form neutral salt. Weak acid react with strong bases to form basic salts whose aq. solution turned red limus blue, phenolphthalein pink and universal indicator blue. Acidic salts are formed by strong acids and weak bases. Crystalline salts are hydrated and loose water of crystallisation on heating, may change colour and become amorphous (powdery).

(a) What is formula of plaster of paris?

(b) What is composition of baking powder?

(c) What happens when milk of magnesia reacts with sulphuric acid ? Write balanced chemical equation.

OR

(i) Name an indicator used by visually impaired children

(ii) Give one use of bleaching powder.

Question: 38.  Photosynthesis can be defined as the synthesis of organic compounds from carbon dioxide and water using solar energy by chlorophyll molecules. In plants, during night carbon dioxide is released by the process of respiration while during daytime carbon dioxide released is used in photosynthesis, hence only oxygen is released. Unlike plants, animals carry out the process of respiration only in the presence of oxygen. This oxygen combines with the digested food and helps in the process of respiration they were releasing large amount of energy.

(a) Stomata of desert plants remain closed during daytime. How do they take up carbon dioxide and perform photosynthesis?

(b) For an efficient digestion in animals, specify the medium required for gastric and pancreatic enzymes to work.

(c) What mode of nutrition is shown by deer? State a reason why a deer will have a longer small intestine than the tiger.

OR

(c) While performing the experiment to prove that carbon dioxide is essential for photosynthesis?

1. Why were the two potted plants kept in dark for 48 hours.
2. If a watch glass containing KOH was kept inside along with pot k what would be the result?

Question: 39.  Smita was unable to see distinctly words written on the blackboard of her classroom from her seat and had to come closer to the blackboard to read the words clearly. So she got her eyes tested in a clinic. The doctor suggested her to use spectacles with lenses. Smith also observed that her Grandfather uses spectacles while reading newspapers but removes the spectacles while doing his routine work.

(a) Which defect of eye is Smita suffering from? Which type of corrective lens, ftstr can be used by Smita?

(b) List two causes for the eye defect Smita is suffering from.

(c) Find the power of the lenses used by Smita if she cannot see beyond 1.5 m.

OR

With the help of a ray diagram describe how this defect of vision can be corrected by using an appropriate lens.