CBSE(NCERT) GRADE 10 SCIENCE 2024 COMPARTMENT SET3

A hydrocarbon which contains two C–C single bonds and one C\equiv C triple bond is:

When aqueous solutions of barium chloride and sodium sulphate react together, an insoluble substance along with aqueous solution of sodium chloride is formed. This reaction is an example of a:

The opening and closing of stomatal pore depends upon:

In bread mould, the structures labelled A and B respectively are:

Which of the following statements is/are true about a neuron?

A doctor advised a person to take an injection of insulin because:

The image formed by a concave mirror of focal length 50 cm is real and of magnification $-1$. In this case the distance between the object from its own image is:

In plants, waste products like resins and gums are stored in:

A person is advised to use lenses of power $-0.25\,\text{D}$ for the correction of his defect of vision. It implies that the person is suffering from:

Biomagnification refers to the increase in the:

In an ecosystem, the amount of energy of sunlight captured by green plants to convert it into food energy is:

The experimental set-up, shown in the diagram, is used for testing the conductivity of a solution filled in the beaker. If we have four solutions, namely solutions of A – sugar, B – common salt, C – lemon juice and D – alcohol and fill them in the beaker one by one to test their conductivity, in which case/cases will the bulb glow ? Give reason to justify your answer.

(a) In the diagram given below, name the labelled parts X and Y. Mention one function for each. OR Graphite rod Solution X Y

List two ways due to which variations arise in a population. State the importance of variation.

(a) Draw a ray diagram to show the formation of a rainbow in

Draw a ray diagram to show the formation of a rainbow in the sky. Mark on the diagram three points A, B and C as given below: A – where dispersion of light occurs; B – where internal reflection of dispersed light occurs; C – where refraction of dispersed light occurs.

Name the muscles present in the human eye which enable it to focus on objects at varied distances (i.e., distant as well as nearby objects). Explain how it happens.

Draw a ray diagram to show the formation of a virtual image of an object placed between the focus and the pole of a concave mirror.

Draw a labelled ray diagram to show the formation of image due to a concave mirror when an object is placed between its pole and principal focus.

List any food chain having four trophic levels. Name the secondary consumer and tertiary consumer in this food chain.

Write an aquatic food chain with four tropic levels. Name the primary and tertiary consumer present in this food chain.

A plant having blue coloured flowers $(BB)$ is crossed with a plant having white coloured flowers $(bb)$: (a) Name the term used for the trait, which is observed in $F_1$ generation. Give its gene combination. (b) If the plants obtained in $F_1$ generation are self-pollinated, write the percentage of (i) plants with flowers of blue colour, and (ii) plants with flowers of white colour in $F_2$ generation. What did the reappearance of plants with white coloured flowers in $F_2$ generation indicate?

(a) Study the experimental set-up shown in the diagram and answer the questions that follow: (i) Name the gas evolved and write the change observed in the lime water. Write chemical equation of the reaction. (ii) If the same gas is passed in excess in the product of the above reaction, what change is observed in the contents of the test tube? Write the chemical formula of the new product formed. OR Dil. Hydrochloric acid + Sodium carbonate Lime water

(a) Write one function each of ovary and testis in the human reproductive system. (b) Give reason why: (i) testes are located outside the abdominal cavity. (ii) lining of the uterus becomes thick every month.

(a) Write the chemical equation of the displacement reaction in which a change in colour is observed when a piece of another metal is dipped in the solution of the salt of a metal. (b) When hydrogen gas is passed over copper(II) oxide, copper and water are formed. Write the balanced chemical equation of this reaction with physical states.

(a) Write a chemical equation for the reaction in which change in colour is observed when a metal is kept immersed in a salt solution of another metal. (b) When hydrogen gas is passed over heated copper(II) oxide, copper and steam are formed. Write the balanced chemical equation with physical states for this reaction. State what kind of chemical reaction is this.

(a) State (i) right-hand thumb rule, and (ii) Fleming’s left-hand rule. (b) Using Fleming’s left-hand rule determine the direction of force experienced by a proton, which enters vertically downwards in a uniform magnetic field acting horizontally from west to east as shown in the diagram.

In the given circuit when key is closed, determine the following: (i) Total resistance offered by the three resistors (ii) Reading of the ammeter (iii) Reading of the voltmeter

(a) Study the following ray diagram and name the angles given below: ∠PEN, ∠FEN¢, ∠SFM and ∠FGH (b) In this diagram, if $\frac{\sin \angle PEN}{\sin \angle FEN} = \frac{3}{2}$, what is the value of $\frac{\sin \angle SFM}{\sin \angle EFM}$? Give reason to justify your answer.

(a) (i) Study the diagram below of alimentary canal of man and name the parts marked as A, B and C. Write the name of the enzyme present in each labelled part. (ii) Explain how digested food reaches each and every cell of the body and is utilised. OR (b) (i) Study the diagram below showing schematic representation of transport and exchange of gases in human heart and name the parts labelled as A, B and C. Mention the function of each part. (ii) Explain how separation of right and left side of the heart is useful for birds.

(a) Write electronic configurations of two elements X (At. no. 12) and Y (At. no. 17). Show the formation of ionic compound when X and Y combine with each other. Write the name and formula of the compound formed. State what would happen if electric current is passed through the aqueous solution of this compound. Name the ion that will reach at (i) cathode, and (ii) anode. OR (b) (i) Write the name of two metals of moderate reactivity. Which one of the two is more reactive? How can this fact be demonstrated experimentally in a school laboratory? (ii) Some metals of moderate reactivity are also found in the Earth’s crust in the form of their carbonates. Name the processes involved in the extraction of metal from them, giving chemical equations for the reactions that occur.

(a) (i) State Ohm’s law. Draw $V$–$I$ graph for an ohmic conductor. (ii) Electrical resistance of a metal wire of length $1\,\text{km}$ is $200\,\Omega$. If the area of cross-section of the wire is $40 \times 10^{-8}\,\text{m}^2$, determine the electrical resistivity of the material of the wire. OR (b) (i) You have three resistors of resistance $R_1$, $R_2$ and $R_3$. If the equivalent resistance of series and parallel combination of the three resistors are $R_s$ and $R_p$ respectively, write the relationship to determine $R_s$ and $R_p$ in terms of $R_1$, $R_2$ and $R_3$. (ii) On the basis of the given circuit answer the questions given below:

Ethanol (commonly known as alcohol) is an important carbon compound widely used in industries, hospitals, etc. Because it is a very good solvent, it is used in medicines such as cough syrups, tincture iodine and many tonics. As it is a cleaner fuel, ethanol is used as an additive in petrol in most of the developed countries of the world. (a) Write the structure of ethanol. (b) Name the products formed when ethanol burns in sufficient air (oxygen). (c) (i) State what happens when 5% solution of alkaline potassium permanganate is added to warm ethanol. Draw the structure of the product formed and state the role of 5% solution of alkaline potassium permanganate in the reaction. OR (c) (ii) State what happens when ethanol is heated with excess conc. H2SO4 at 443 K. Draw the structure of the product formed and state the role of conc. H2SO4 in the reaction.

An object is placed at a distance of 12 cm from the optical centre of a convex lens of focal length 18 cm. Draw a labelled ray diagram to show the formation of image in this case.

Plantation drives are often carried out especially during monsoon season for the protection of our environment. Such programmes need a lot of saplings for tree plantation. Plants are propagated by sexual or asexual means in fields and nurseries. Over the years horticulturists have developed asexual methods that use vegetative parts of the plants to multiply. Many plants can reproduce by this method naturally as well as by artificial means. (a) Which specific part of the plant is used for sexual and asexual means of propagation to produce a new plant? (b) Give one example of (i) a flower, and (ii) a fruit grown by vegetative propagation. (c) (i) List two advantages of growing plants by vegetative propagation. OR (c) (ii) How are potato plants grown by asexual reproduction? Give one example.

The image formed by a convex lens is real, inverted and of the same size as the object. If the distance between the object and the image is 60 cm, determine the focal length of the lens. Give justification for your answer.

We use compound microscopes in laboratories to examine the enlarged image of a microscopic object. A compound microscope has two lenses, one objective lens and one eyepiece lens. The objective lens forms a real, inverted and enlarged image of the object, which acts as the object for the eyepiece lens. The eyepiece lens acts as a magnifying glass and forms a final enlarged virtual image of the object. (a) Which lens of the compound microscope forms the real image? (b) Which lens acts as a magnifying glass? (c) (i) Draw a ray diagram of a compound microscope when an object is placed at 12 cm from the optical centre of a convex lens of focal length 18 cm. OR (c) (ii) Using a lens of focal length $f$, a virtual, erect and same-sized image is formed. If the distance between the object and its image is 60 cm, determine the focal length of the lens. Give reason for your answer.

(a) The image of an object formed by a convex lens of focal length 2 cm is real, inverted and magnified. What is the range of object distance in this case?