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Some Basic Concepts of Chemistry · Question 30

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1

0.1 mol of the following given antiviral compound (P) will weigh 10-1 g (nearest integer). [figure] (Given : molar mass in g mol-1 H : 1, C : 12, N : 14, O : 16, F : 19, I : 127)

Answer

372

Solution

Counting the atoms of (P):

Base ring (5-iodouracil part): 4 C, 2 N, 2 O, 1 I and 2 H (N–H and C6–H)

Sugar part: 5 C, 3 O (ring O and two –OH), 1 F and 8 H (C1′–H, C2′–H, C3′–H, C4′–H, CH2 (2 H), two O–H)

Molecular formula of P = C9H10FIN2O5

Molar mass = 9(12) + 10(1) + 19 + 127 + 2(14) + 5(16)

= 108 + 10 + 19 + 127 + 28 + 80 = 372 g mol-1

Mass of 0.1 mol = 0.1 372 = 37.2 g = 372 10-1 g

Answer: 372

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2

'x' g of NaCl is added to water in a beaker with a lid. The temperature of the system is raised from 1 C to 25 C. Which out of the following plots, is best suited for the change in the molarity (M) of the solution with respect to temperature? [Consider the solubility of NaCl remains unchanged over the temperature range]

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
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3

Choose the correct statements. Choose the correct answer from the options given below :

  1. (B), (C) and (D) Only
  2. (A), (B) and (C) Only
  3. (C), (D) and (E) Only
  4. (A), (D) and (E) Only
JEE Main 2025 (Online) 29th January Morning Shift
4

The molarity of a 70\% (mass/mass) aqueous solution of a monobasic acid (X) is 10-1 M (Nearest integer) [Given: Density of aqueous solution of (X) is 1.25 g mL-1 Molar mass of the acid is 70 g mol-1]

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5

Quantitative analysis of an organic compound (X) shows following % composition. C : 14.5\% Cl : 64.46\% H : 1.8\% Empirical formula mass of the compound (X) is 10-1 (Given molar mass in g mol-1 of C : 12, H : 1, O : 16, Cl : 35.5)

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6

Concentrated nitric acid is labelled as 75% by mass. The volume in mL of the solution which contains 30 g of nitric acid is . Given : Density of nitric acid solution is 1.25 g/mL.

  1. 32
  2. 40
  3. 55
  4. 45
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