Question

A 500 g toothpaste sample has `0.2` g fluoride concentration. What is the concentration of `F^(Theta)` in ppm ?
A. 250
B. 200
C. 400
D. 1000

Answer 1

Correct Answer - C
ppm of `F`
`=("wt. of" F)/("wt. of paste") xx 10^(6)=(0.2)/("wt. of paste") xx 10^(6) = (0.2)/(500)xx10^(6)=400` .