A water sample has ppm level concentration of following anions
`F^(-)=10 , SO_(4)^(2-)=100 , NO_(3)^(-) =50`
the anion/anions that make/makes the water sample unsuitable for drinking is/are

Options

A. only `F^-`
B. only `SO_4^(2-)`
C. only `NO_3^-`
D. both `SO_4^(2-)` and `NO_3^(-)`

Answer

A

Explanation

Acceptable level of `F^-` is upto 1 ppm, `NO_3^-` is upto 50 ppm and `SO_4^(2-)` is upto 500 ppm `F^-` concentration in water sample is 10 ppm which is higher than the permissible level. Therefore, only `F^-` makes the water sample unsuitable for drinking