Day 71: JEE Mains Chemistry

Equilibrium. This type asked 3 times: 25 Jul 2022, 26 Jul 2022, 8 Apr 2023. This one: 8 Apr 2023 See all 3 of this type

58

The titration curve of weak acid vs. strong base (with phenolphthalein as indicator) is shown below. The $K_{\text{phenolphthalein~}}= 4 \times10^{- 10}$. Given: $\log2 = 0.3$ The number of following statements which is/are correct about phenolphthalein is___ (A) It can be used as an indicator for the titration of weak acid with weak base. (B) It begins to change colour at $pH = 8.4$ (C) It is a weak organic base (D) It is colourless in acidic medium

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Equilibrium. This type asked 3 times: 2021 Paper 24, 29 Jun 2022, 8 Apr 2023. This one: 8 Apr 2023 See all 3 of this type

Haloalkanes and Haloarenes. This type asked 3 times: 2021 Paper 2, 25 Jan 2023, 8 Apr 2023. This one: 8 Apr 2023 See all 3 of this type

138

The correct order of reactivity of following haloarenes towards nucleophilic substitution with aqueous $NaOH$ is: (A) (B) (C) (D) Choose the correct answer from the options given below:

1. A.
   A $>$ B $>$ D $>$ C
2. B.
   C $>$ A $>$ D $>$ B
3. C.
   D $>$ C $>$ B $>$ A
4. D.
   D $>$ B $>$ A $>$ C

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Some Basic Concepts of Chemistry. This type asked 3 times: 2021 Paper 25, 29 Jun 2022, 8 Apr 2023. This one: 8 Apr 2023 See all 3 of this type

The d- and f-Block Elements. This type asked 3 times: 30 Jan 2023, 1 Feb 2023, 6 Apr 2023. This one: 6 Apr 2023 See all 3 of this type