JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 18 March 2021, Shift 1, Chemistry Q59

Question 59 of 90 in this shift, Chemistry question 29 of 30, Section B.

__________ grams of 3-Hydroxy propanal (MW = 74) must be dehydrated to produce 7.8 g of acrolein (MW = 56) (

\mathrm{C_3H_4O}

) if the percentage yield is 64. (Round off to the Nearest Integer). [Given : Atomic masses : C : 12.0 u, H : 1.0 u, O : 16.0 u]

Official answer

NTA final key.

Chapter: Aldehydes, Ketones and Carboxylic Acids
Topic: Stoichiometry
Idea tested: Reverse Yield Calculation

Same topic in other shifts

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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. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.