Question

An advice is given by the government of India to all the pharmaceutical companies for the manufacture of a medicine having a concentration of 2700 ppb used for treating Covid-19 patients. The concentration of medicine in %(w/w) is:

• A. $2.7\times {10}^{-4}$
• B. $6.5\times {10}^{-4}$
• C. $3.2\times {10}^{-3}$
• D. $6.5\times {10}^{-3}$

Answer 1

The correct option is A $2.7\times {10}^{-4}$

$partperbillion=\frac{massofsolute}{massofsolution}\times {10}^9$
$\frac{massofsolute}{massofsolution}=\frac{partsperbillion}{{10}^9}$
$masspercentage=\frac{massofsolute}{massofsolution}\times 100$
$masspercentage=\frac{givenvalueinppb}{{10}^9}\times 100$
$=\frac{2700}{{10}^9}\times 100=2.7\times {10}^{-4}\%\left(w/w\right)$