(A) Fill in the blanks by choosing the appropriate word(s) from those given in the [4×1] brackets: [four, three, remains same, propane, ns1-2, increases, six, propan-2-ol, (n-1)d1-10, two, decreases, Clemmensen’s, Wolff-Kishner]
Given below are two statements marked Assertion and Reason. Read the two
statements carefully and select the correct option.
Assertion: There is a continuous increase in size among Lanthanoids with an
increase in atomic number.
Reason: Lanthanoids do not show Lanthanoid contraction.

1. Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
2. Both Assertion and Reason are true but Reason is not the correct explanation for assertion.
3. Assertion is true but Reason is false.
4. Both Assertion and Reason are false. (C) Read the passage carefully and answer the questions that follow. [3×1] A plant or any other living being maintains a reasonable balance of C-14 (radioactive carbon) in its tissue during its lifetime. C-14 is used to determine the age of fossils. In the upper atmosphere, neutrons present in the cosmic rays are captured to produce the following nuclear reaction. 7N + 0n1 6C + 1H1 C-14 isotope is circulated in the atmosphere and gets absorbed by living organism during photosynthesis. The ratio of C-14 to C-12 in living being is 1:1012. Once the living being dies, the level of C-14 in the dead being decreases due to the following reaction. 6C 7N + -1e0 + γ rays The death of the plant brings an end to its tendency to take up C-14. The half- life period of C-14 is 5770 years. By knowing the concentration of C-14 in the living plant and the piece of dead material at a particular time, the age of the material (fossil) can be determined.

Specimen paper · 2025 · CollegeDekho (mirror of CISCE PDF)