A water sample has ppm level concentration of the following metals: $\mathrm{Fe}=0.2, \mathrm{Mn}=5.0, \mathrm{Cu}=3.0, \mathrm{Zn}=5.0$. The metal that makes the water sample unsuitable for drinking is

JEE Main · 2019 · 09 Jan 2019 · Shift 1 · Environmental Chemistry

A water sample has ppm level concentration of the following metals:

Fe = 0.2, Mn = 5.0, Cu = 3.0, Zn = 5.0

. The metal that makes the water sample unsuitable for drinking is

Answer: (B)

Compare each concentration with its safe drinking-water limit. Iron at

0.2

, copper at

3.0

and zinc at

5.0

ppm sit at or within their permissible limits, but manganese's limit is only about

0.05

ppm, and here it stands at

5.0

ppm, a hundred times too high. Manganese is what renders the sample unfit to drink.

JEE Main · 2019 · 09 Jan 2019 · Shift 1 · Single correct option