CBSE conducted the class 10 science board examination of 20th February 2025 and you can check and download the question paper and answer key from here.
CBSE Class 10 Board Exam 2025
SCIENCE Question Paper and Answer key
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- The most common method of extraction of metals from their oxide ores is:
(A) Reduction with carbon- Explanation: Carbon is widely used as a reducing agent to extract metals from their oxide ores because it is cheap and readily available.
- Explanation: Carbon is widely used as a reducing agent to extract metals from their oxide ores because it is cheap and readily available.
- To balance the chemical equation pAl+qH2O→rAl2O3+sH2, the values of p,q,r,p,q,r, and ss are:
(C) 2, 3, 1, 3- Explanation: The balanced equation is 2Al+3H2O→Al2O3+3H2
- Explanation: The balanced equation is 2Al+3H2O→Al2O3+3H2
- Select the two structures which are related to each other:
(D) (i) and (iii)- Explanation: Both structures (i) and (iii) represent hydrocarbons with similar bonding patterns.
- Explanation: Both structures (i) and (iii) represent hydrocarbons with similar bonding patterns.
- Incorrect statement about hydrogenation of vegetable oils:
(D) It is an addition reaction which occurs in the presence of an acid catalyst.- Explanation: Hydrogenation of vegetable oils occurs in the presence of a nickel or palladium catalyst, not an acid catalyst.
- Explanation: Hydrogenation of vegetable oils occurs in the presence of a nickel or palladium catalyst, not an acid catalyst.
- Option representing a family of salts:
(B) K₂SO₄, Na₂SO₄, CaSO₄- Explanation: All these compounds are sulfates, which belong to the same family of salts.
- Explanation: All these compounds are sulfates, which belong to the same family of salts.
- Pair of bisexual flowers:
(B) Hibiscus and mustard- Explanation: Bisexual flowers contain both male (stamen) and female (pistil) reproductive organs. Hibiscus and mustard are examples of bisexual flowers.
- Explanation: Bisexual flowers contain both male (stamen) and female (pistil) reproductive organs. Hibiscus and mustard are examples of bisexual flowers.
- Growth of pollen tubes towards ovules is an example of:
(D) Chemotropism- Explanation: Chemotropism is the growth of a plant part in response to a chemical stimulus. Pollen tubes grow towards ovules due to chemical signals.
- Explanation: Chemotropism is the growth of a plant part in response to a chemical stimulus. Pollen tubes grow towards ovules due to chemical signals.
- Match Column-I with Column-II:
(D) a-(iii), b-(ii), c-(i), d-(iv)- Explanation:
- a. Site of fertilization: Oviduct (iii)
- b. Site of implantation: Uterus (ii)
- c. Site of entry of sperm: Vagina (i)
- d. Site for waste removal: Placenta (iv)
- Explanation:
- Plant hormone present in greater concentration in rapidly dividing cells:
(B) Cytokinins- Explanation: Cytokinins promote cell division and are found in high concentrations in areas of rapid cell division.
- Explanation: Cytokinins promote cell division and are found in high concentrations in areas of rapid cell division.
- Parasitic mode of nutrition is observed in:
(C) Cuscuta- Explanation: Cuscuta (dodder) is a parasitic plant that derives its nutrition from the host plant.
Complete question paper with answer key in PDF format is available here
