Science 36/6/3 2024-2025 English Medium Class 10 Question Paper Solution

Examples of thermal decomposition reactions are:

1. \[\ce{2AgCl->2Ag + Cl2}\]
2. \[\ce{CaCO3->CaO + CO2}\]
3. \[\ce{2H2O->2H2 + O2}\]
4. \[\ce{2KClO3->2KCl + 3O2}\]

(i) and (ii)

(ii) and (iii)

(iii) and (iv)

(ii) and (iv)

You have three aqueous solutions A, B and C as given below:

1. Potassium nitrate
2. Ammonium chloride
3. Sodium carbonate

The ascending order of the pH of these solutions is:

A < B < C

B < C < A

C < A < B

B < A < C

Which one of the following metals is protected from corrosion by a layer of its own oxide?

Aluminium

Copper

Silver

Gold

The colour of the solution observed after about 1 hour of placing iron nails in copper sulphate solution is ______.

Blue

Pale green

Yellow

Reddish brown

A hydrocarbon which does not belong to the same homologous series of carbon compounds is ______.

C₄H₁₀

C₆H₁₄

C₇H₁₄

C₁₀H₂₂

The water of crystallization is present in ______.

1. Bleaching Powder
2. Plaster of Paris
3. Washing Soda
4. Baking Soda

(ii) and (iv)

(ii) and (iii)

(i) and (iii)

(i) and (iv)

Juice of tamarind turns blue litmus to red. It is because of the presence of an acid called ______.

methanoic acid

acetic acid

tartaric acid

oxalic acid

Electrical impulse travels in a neuron from:

Nerve ending → Axon → Cell body → Dendrite

Dendrite → Cell body → Axon → Nerve ending

Cell body → Dendrite → Axon → Nerve ending

Dendrite → Axon → Nerve ending → Cell body

A tall pea plant with round seeds (TTRR) is crossed with a short pea plant with wrinkled seeds (ttrr). The F₁ generation will be ______.

25% tall with round seeds

50% tall with wrinkled seeds

75% tall with wrinkled seeds

100% tall with round seeds

The basic filtration unit of the excretory system in human beings is ______.

Nephron

Urethra

Neuron

Urinary bladder

Which one of the following is not an excretory product in plants?

CO₂

Starch

Resins and gums

Dead cells

In human alimentary canal, the digestive juice secreted by the gastric glands are ______.

Bile, Trypsin, Pepsin

Hydrochloric acid, Pepsin, Mucus

Lipase, Bile, Mucus

Salivary amylase, Pepsin, Bile

The curvature of eye lens of human eye ______.

is fixed.

can be increased.

can be decreased.

increases or decreases as the case may be.

Identify from the following the ray diagram which shows the correct path of the reflected ray for the ray incident on a concave mirror, as shown:

In the following groups of wastes, which group contains only non-biodegradable wastes?

Leather footwear, Plastic plate, Polythene bag

Empty medicine bottle, Milk packet, Aluminium can

Used tea leaves, Cardboard box, Iron nail

Plastic Syringes, Newspaper, Ball point pen

Consider the following food chain:

Grass → Grasshopper → Frog → Snake → Eagle

If the amount of energy available at third trophic level is 50 kJ, the available energy at the producer level was:

0.5 kJ

5 kJ

500 kJ

5000 kJ

Assertion (A): Xylem tissue moves water and minerals obtained from the soil by the roots.

Reason (R): Xylem tissue is found only in the roots of a plant. 

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

Both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of the Assertion (A).

Assertion (A) is true, but Reason (R) is false.

Assertion (A) is false, but Reason (R) is true.

Assertion (A): Carbon and its compounds are our major sources of fuels.

Reason (R): Most of the carbon compounds on burning release a large amount of heat and light.

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

Both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of the Assertion (A). 

Assertion (A) is true, but Reason (R) is false. 

Assertion (A) is false, but Reason (R) is true.

Assertion (A): Food web is a network of several food chains operating in an ecosystem.

Reason (R): Food web decreases the stability of an ecosystem.

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

Both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of the Assertion (А).

Assertion (A) is true, but Reason (R) is false.

Assertion (A) is false, but Reason (R) is true.

Assertion (A): In the common domestic circuits the earth wire is connected to a metallic plate buried deep inside the earth.

Reason (R): Earth wire ensures that any leakage of current to the metallic body of the appliance keeps its potential to that of the earth, so the user may not get a severe electric shock.

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

Both Assertion (A) and Reson (R) are true and Reason (R) is not the correct explanation of the Assertion (A).

Assertion (A) is true, but Reason (R) is false.

Assertion (4) is false, but Reason (R) is true.

Name a metal found in the earth’s crust in free state and state where each of these metals is placed in the reactivity series of metals.

Name a metal found in the earth’s crust in the form of its compound state, where each of these metals is placed in the reactivity series of metals.

Study the figure in which the path of a ray of light going from Medium 1 to Medium 2 is shown.

1. Out of the two Media - Medium 1 and Medium 2, in which is the speed of light more?
2. State reason of bending of the refracted ray away from the normal.
3. Express refractive index of Medium 2 with respect to Medium 1 in terms of speed of light in two media.

Give reasons:

The sky appears dark to passengers flying at very high altitude.

Give a scientific reason:

Danger signals are red in colour.

What is a rainbow?

“Proteins control the expression of various characters.” Explain this statement by taking the example of “tallness” as a characteristic in plants.

Explain the mechanism of inheritance used by sexually reproducing organisms to ensure the stability of DNA of the species.

How is brain protected in our body?

A doctor finds in one of his patients that he is not maintaining a proper posture and balance of his body. State the region of brain and also the part of brain which is responsible for it.

Write the percentage of the energy of sunlight captured by green plants to convert it into food energy. Explain the fate of this energy when green plants are eaten by primary consumers.

Why is respiration considered an exothermic reaction? Explain.

State the chemical property in which the following uses of baking soda are based upon as an anti-acid.

State the chemical property in which the following uses of baking soda are based upon as a constituent in making baking powder.

State the chemical property in which the following uses of baking soda are based upon in soda-acid fire-extinguishers.

Write chemical equations to show what happens when an acid reacts with a metal; also write the name of the main product formed.

Write chemical equations to show what happens when an acid reacts with a base; also write the name of the main product formed.

Write chemical equations to show what happens when an acid reacts with a carbonate; also write the name of the main product formed.

A student placed a candle flame at different distances from a convex lens and focused its image on a screen. He recorded his observation in tabular form as given below:

Analyse the observation table and on the basis of your analysis only, answer the following questions (without doing any calculations):

1. What is the focal length of the convex lens used? Give reason to justify your answer.
2. Which one of the sets of observations is not correct and why?
3. Draw ray diagram to show image formation for any correct set of observation. 

“In human beings, the genes inherited from the parents decide whether the newborn individual is male or female.”

Explain this statement with the help of a flow diagram.

“Some animals rely on environmental cues for sex determination.” Justify this statement giving an example.

Name the blood vessel that brings oxygenated blood to the human heart.

Name the blood vessel that brings deoxygenated blood to the human heart.

Name the chamber of the heart which receives deoxygenated blood and state how deoxygenated blood from this chamber is sent to the lungs for oxygenation.

A person uses lenses of power −0.5 D in his spectacles for the correction of his vision.

1. Name the defect of vision the person is suffering from.
2. List two causes of this defect.
3. Determine the focal length of the lenses used in the spectacles.

Explain the statement ‘the potential difference between two points is 1 volt’.

What does the symbol given below represent in an electric circuit? Write one function.

What does the symbol given below represent in an electric circuit? Write one function.

How is the direction of magnetic field at a point determined?

Draw the pattern of magnetic field lines of the magnetic field produced by a current carrying circular loop. Mark on it the direction of (i) current and (ii) magnetic field lines.

Name the two factors on which the magnitude of the magnetic field due to a current carrying coil depends.

Why can't two magnetic field lines cross each other?

Draw magnetic field lines showing the direction of the magnetic field due to a current carrying long straight solenoid. State the conclusion which can be drawn from the pattern of magnetic field lines inside the solenoid.

Name any two factors on which the magnitude of the magnetic field due to this solenoid depends. 

Mention the common method of reproduction in Amoeba.

Name the method by which Leishmania reproduce.

Write a major difference in the way Amoeba and Leishmania divide to produce new individuals.

What is meant by asexual reproduction? 

Explain the process of budding in Hydra.

Give two methods used to grow rose plants by vegetative propagation.

Give two methods used to grow jasmine plants by vegetative propagation.

Write one function of the petals of a bisexual flower.

Write one function of the anther of a bisexual flower.

Write one function of the style of a bisexual flower.

Write one function of the ovary of a bisexual flower.

Give one example of a unisexual flower.

Give one example of a bisexual flower.

Mention the changes a flower undergoes after fertilisation.

Name an alcohol and a carboxylic acid having two carbon atoms in their structures. Draw their structures and state how this alcohol can be converted into a carboxylic acid. What happens when these two compounds react in the presence of an acid? Write chemical quations for the reactions involved in the two cases mentioned above.

What are soaps?

Write the structure of a soap molecule.

Explain the cleansing action of soaps.

Why are soaps not considered suitable for washing clothes in a region where water is hard? How is this problem overcome?

1. How does electrical conductivity and melting point of a metal change when it is converted to its alloy by mixing a small amount of an element in it?   (1)
2. Name an alloy used for welding two wires together in an electric circuit. Write its major constituents.   (1)
3. 1. What are alloys? How is ‘Brass’ (an alloy) prepared?   (2)
      OR
   2. What is stainless steel? How is it prepared? Write one important property which makes it more useful in making cooking utensils as compared to its primary metal.   (2)

1. Name the movement which causes ‘X’ and ‘Y’ to grow downwards and upwards respectively.   (1)
2. Write the name of a hormone that plays a major role in
   1. falling of leaves.
   2. rapid cell division.  (1)
3. 1. Leaves of the sensitive plant move very quickly in response to ‘touch’. How is this stimulus of touch communicated and explain how the movement takes place?  (2)
      OR
   2. Name the plant hormone which is synthesized at the shoot tip. How does this hormone help the plant to bend towards light?  (2)

Study the circuit shown in which two resistors X and Y of resistances 3 Ω and 6 Ω respectively are joined in series with a battery of 2 V.

1. Draw a circuit diagram showing the above two resistors X and Y joined in parallel with the same battery and the same ammeter and voltmeter.  (1)
2. In which combination of resistors will the (i) potential difference across X and Y and (ii) current through X and Y, be the same?  (1)
3. 1. Find the current drawn from the battery by the series combination of the two resistors (X and Y).  (2)
      OR
   2. Determine the equivalent resistance of the parallel combination of the two resistors (X and Y).  (2)