Question

500 milliliters of solution of 0.1 M NaBr has how many milligrams of bromine?

• A. $200mg$
• B. $400mg$
• C. $2,000mg$
• D. $4,000mg$
• E. $20,000mg$

Answer 1

The correct option is D $4,000mg$

Number of moles $=$ molarity $\times$ volume $=0.1M\times 0.5L=0.05moles$
Mass of 0.05 moles of $B{r}^{-}=$ molecular weight $\times$ moles $=80g/mol\times 0.05mole=4g=4000mg$