The most abundant elements by mass in the body of a healthy human adult are : Oxygen (61.4%); Carbon (22.9%), Hydrogen (10.0%); and Nitrogen (2.6%). The weight which a 75 kg person would gain if all H atoms are replaced by H atoms is :
← JEE Main 2017 · 2 Apr · Shift 1
ChemistrySingle correct+4 / -1Question 49 of 90
JEE Main 2017 · 2 Apr · Shift 1, Chemistry question 49
Answer and worked solution
Official answer: A
Hydrogen is 10% of 75 kg, i.e. 7.5 kg. Replacing ¹H by ²H doubles that mass, so the person gains 7.5 kg.
Topics:Mole concept