CBSE Extra Questions For Class 10 Science

CBSE Class 10 Science Extra Questions

Students who are preparing for the upcoming board exams can find CBSE Class 10 science extra questions on Extramarks. It will aid them in their preparation for the CBSE Class 10 board, the state board and various other matriculation level exams. 

Importance of Extra Questions for CBSE Class 10 Science (include chapter wise extra questions)

The key to crack any exam is sheer practice. Students should practice and solve important questions. This will help them nurture their problem solving abilities as well as give them an edge in scoring better in exams. Extramarks has listed chapter wise important questions which will help them prepare better: 

Chapter 1: Chemical Reactions and Equations 

• What occurs chemically when the quick lime is introduced to water?
• Why are food particles packaged in aluminum foil?
• What happens to lime water when a large amount of CO2 gas is bubbled through it?
• What exactly is a neutralisation reaction? What is the significance of their names? Can you give an example?
• A student dropped a few marbles into a test tube containing dilute hydrochloric acid. After that, the evolved gas was passed via lime water. What difference might be seen in lime water? Write a balanced chemical equation for both the observed changes.

Chapter 2: Acids Bases, and Salts 

• Can you describe the process by which you will prove that acetic acid is a monobasic acid?
• An aqueous solution’s pH lowers from 3 to 2. What will happen to the solution’s nature?
• Compound A’ solution was colored pink when phenolphthalein indicator was added. How can this be explained?
• What color will a basic solution acquire if a few drops of indicator methyl orange are added to it?
• If baking soda is heated, what is the chemical formula of the main product generated?

Chapter 3: Metals and Non-metals 

• What’s the distinction between calcination and roasting?
• How do the compositions of the alloys brass and bronze differ?
• What happens when manganese dioxide is heated with aluminum powder?
• Rather than pure metals, alloys are employed in electrically heating equipment. Give an explanation.
• What is the consistent theme of metal atoms’ electronic configuration?

Chapter 4: Carbon and its Compounds 

• Why is the flame of a candle often yellow?
• What function does soap play in the cleaning of clothes?
• Why is there such a high concentration of organic compounds?
• Which of the ketonic and aldehydic functional groups is the terminal functional group?
• With ethanol and concentrated sulphuric acid, what do we get when ethanoic acid interacts with ethanol?
• Bromine dissolved in carbon tetrachloride was passed through a hydrocarbon vapour. Where did the yellow color of bromine come from? Predict the hydrocarbon’s nature.

Chapter 5: Periodic Classification of Elements 

• State three elements that exhibit metalloid properties.
• Reveal the identity of the second alkali metal as well as its electrical configuration.
• Write the electrical configuration of the atom in the periodic table’s third period and seventeenth group.
• Three elements, X, Y, and Z, are members of the 17th group but belong to the 2nd, 3rd, and 4th periods, respectively. Y has a total of seven valence electrons. Determine the total number of valence electrons in X and Z.
• Identify the members of the alkaline earth family. Which of them is naturally radioactive?
• MgO is the chemical formula for magnesium oxide. Write the magnesium chloride formula.

Chapter 6: Life Processes 

• What function does saliva play in food digestion?
• Which pancreatic enzyme is most effective in protein digestion?
• Where does fat digestion occur in our bodies?
• In a plant, identify the tissue that carries soluble photosynthetic products.
• Specify the blood component that aids in the development of a blood clot in the case of a wound.

Chapter 7: Control and Coordination

• Define the term chemotropism.
• What exactly are phytohormones?
• What is the name of the gland that secretes growth hormone?
• Which hormone is responsible for the growth of a man’s moustache and beard?
• What is the purpose of the hormone released by the pituitary endocrine gland?
• Identify the following tissues in multicellular creatures that offer control and coordination.

Chapter 8: How do Organisms Reproduce 

• Describe the procedure utilised to develop rose plants.
• List two roles of the ovaries in a female person.
• Why is DNA replication such an important aspect of the reproduction process?
• Name the life process of an organism that aids in population increase.
• Name the hormone whose production is responsible for substantial changes in  appearance in females between the ages of 10 and 12.

Chapter 9: Heredity and Evolution 

• Who came up with the theory of natural selection?
• What role do genes play in an organism?
• Make a list of any two criteria that might result in speciation.
• A green plant is always the initial trophic level in a food chain. Why?
• What exactly are fossils? How do they explain the evolution process?

Chapter 10: Light Reflection and Refraction 

• Mention the characteristics of the picture created by a flat mirror.
• Define the spherical mirror’s primary axis.
• Determine the primary focus of a concave mirror.
• Where on the major axis of a concave mirror should an object be placed to generate a magnified and virtual picture of an object?
• Describe a mirror that produces an upright and magnified (enlarged) picture of an object.

Chapter 11: The Human Eye and the Colorful World 

• What would be the nature of the image created at the human eye’s retina?
• Name the portion of the human eye that aids in the adjustment of the focal length of the eye lens.
• Name the following component of the human eye: A black muscular diaphragm that regulates pupil size.
• What is hypermetropia, often known as farsightedness?
• Draw a ray diagram to demonstrate how an appropriate lens corrects the eye defect myopia.

Chapter 12: Electricity

• Is electric potential a physical quantity that may be expressed as a scalar or a vector quantity?
• What is the name of the instrument that is used to measure the electric potential difference?
• Write out the relationship between the electric current I running through a conductor, the change Q flowing through the conductor, and the time t.
• What is the relationship between the direction of electric current and the direction of electron flow in a wire?
• Create a circuit diagram that shows the relationship between the potential difference at the terminals of a resistor and the current flowing upwards through it.

Chapter 13: Magnetic Effects of Electric Current 

• Why is the magnetic field direction at a given site ascertained?
• What is the definition of a magnetic field line?
• What is the magnetic field line direction outside of a bar magnet?
• Where on the magnet are the magnetic field lines densest?
• What relationship exists between the intensity of the magnetic field around a wire and the strength of the electric current?

Chapter 14: Sources of Energy 

• What is  the primary ingredient of “LPG.”
• Name any two gases produced by the combustion of fossil fuels.
• How is the growth in energy consumption affecting our environment?
• Rationalise hydro power (hydel electricity) as a renewable source of energy in one word.
• Which microorganisms are capable of carrying out the breakdown process in a biogas plant?

Chapter 15: Our Environment 

• Why is the ozone layer depleting at higher heights of the atmosphere?
• What are the two most important elements of our environment?
• Why are green plants referred to as producers?
• Paper packaging is more environmentally friendly than polythene packaging. Demonstrate.
• Describe one benefit of utilising disposable paper cups versus throwaway plastic cups.

Chapter 16: Management of Natural Resources 

• How is the increased demand for energy already harming the air environment?
• Describe a time when human intervention spared a forest from destruction.
• Give one reason why the woods and wildlife should be conserved.
• Mention any two methods you propose for better water resource management.
• Mention one detrimental impact of our prosperous way of life on the environment.