PYQ Vault

Day 93: CBSE Class 10 Science

5 questions. Try each one first, then open its answer.

  1. Question 1

    Metals and Non-metals. Asked once: 2025 (same type asked 3 times)

    22 (B)
    “Aluminium oxide is an amphoteric oxide.” Justify this statement giving chemical equation for the reactions involved.

  2. Question 2

    Metals and Non-metals. Asked once: 2026 (same type asked 3 times)

    25
    Write balanced equations for the reactions of the following : (a) Iron with steam (b) Calcium with water

  3. Question 3

    Metals and Non-metals. Asked once: 2026 (same type asked 3 times)

    26
    Answer the following : (a) Why can the oxides of highly reactive metals not be reduced by carbon ? (b) Why do ionic compounds have high melting and boiling points ? (c) Why is a solder, an alloy of lead and tin, used for welding electrical wires together ?

  4. Question 4

    Metals and Non-metals. Asked once: 2026 (same type asked 3 times)

    27 (A)
    (i) Which method will be used to convert each of them to their respective metal oxides ? (a) Carbonate ore (b) Sulphide ore (ii) Write a chemical reaction to illustrate the use of aluminium for joining cracked railway tracks. (iii) During extraction of metals, electrolytic refining is used to obtain pure metals. Which material will be used as anode and cathode for the refining of copper metal by this process ?

  5. Question 5

    Our Environment. Asked once: 2025 (same type asked 3 times)

    33
    (a) “In a food chain energy flow is unidirectional.” Give two reasons for the given statement. (b) If 10,000 J energy is available at the producer level, how much energy will be available to the secondary consumers ? Give reason to justify your answer.