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JEE Main 2022 · ChemistryNumerical answerNumerical valueMediumData or graph

JEE Main 25 July 2022, Shift 2, Chemistry Q85

Question 85 of 90 in this shift, Chemistry question 25 of 30, Section B.

For the decomposition of azomethane, CH3N2CH3(g)→CH3CH3(g)+N2(g)\mathrm{CH_3N_2CH_3(g) \rightarrow CH_3CH_3(g) + N_2(g)}, a first order reaction, the variation in partial pressure with time at 600 K is given as [figure: graph of ln⁡(pp0)\ln\left(\frac{p}{p0}\right) (y-axis) versus t/s (x-axis), a straight line sloping downward, labelled Slope = −3.465×104-3.465 \times 10^4] The half life of the reaction is ___ ×10−5\times 10^{-5}s. [Nearest integer]

The figure, in words

Straight line falling from a point on the y-axis; y-axis label ln(p/p0), x-axis t/s; label Slope = -3.465 x 10^4.

Official answer

2

NTA final key.

Chapter
Chemical Kinetics
Topic
Integrated Rate Equations
Idea tested
First Order Half-Life

Same idea in other shifts

Asked 6× in all
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  2. 13 Apr 2023, Shift 1 · Q87t87.5t_{87.5} is the time required for the reaction to undergo 87.5% completion and t50t_{50} is the time required for the reaction to undergo…EasyNumerical value
  3. 27 Jul 2022, Shift 2 · Q85[A] →\rightarrow [B] Reactant Product If formation of compound [B] follows the first order of kinetics and after 70 minutes the…EasyNumerical value
  4. 26 Jun 2022, Shift 1 · Q84A flask is filled with equal moles of A and B. The half lives of A and B are 100 s and 50 s respectively and are independent of the…HardNumerical value
  5. 28 Jun 2022, Shift 2 · Q85A radioactive element has a half life of 200 days. The percentage of original activity remaining after 83 days is __________ . (Nearest…MediumNumerical value

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. This question needs a figure we do not reproduce; it is described in words above. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.