PYQ Vault

Day 120: CBSE Class 10 Science

5 questions (8 parts). Try each one first, then open its answer.

  1. Question 1

    Heredity. Asked once: 2024 (same type asked 4 times)

    23 (a)
    List any two pairs of visible contrasting characters of garden pea plants used by Mendel for his experiments stating the dominant and recessive characters in each pair.

  2. Question 2 (case study, 4 parts)

    How do Organisms Reproduce?. Asked once: 2024 (same type asked 4 times)

    Pollination is an important process in sexual reproduction of plants. It is an essential process that facilitates fertilisation in plants. Pollinating agents can be wind, water, insects and birds. Several changes take place in the flower after the fertilization has taken place.
    38 (a)
    Write the main difference between self-pollination and cross-pollination.
    38 (b)
    Name the part of the flower which attracts insects for pollination. What happens to this part after fertilisation ?
    38 (c) (i)
    Define fertilisation. What is the fate of ovules and the ovary in a flower after fertilisation ?
    38 (c) (ii)
    In a germinating seed, which parts are known as future shoot and future root ? Mention the function of cotyledon.

  3. Question 3

    Metals and Non-metals. Asked once: 2023 (same type asked 4 times)

    6
    The number of electrons in the outermost shell of the atom of a non-metal can be :

    Tap an option to check your answer.

  4. Question 4

    Acids, Bases and Salts. Asked once: 2023 (same type asked 3 times)

    28
    (i) Suggest a safe procedure of diluting a strong concentrated acid. (ii) Name the salt formed when sulphuric acid is added to sodium hydroxide and write its pH. (iii) Dry HCl\mathrm{HCl} gas does not change the colour of dry blue litmus paper. Why ?

  5. Question 5

    Acids, Bases and Salts. Asked once: 2023 (same type asked 3 times)

    28 (a)
    (i) What property do acids and bases have in common ? Explain it with an example. (ii) A compound which is prepared from gypsum has the property of hardening when mixed with water. Identify the compound and write its formula. How is this compound prepared ? Describe it in the form of a chemical equation only.