A silver coin weighing `11.34g` was dissolved in nitric acid. When sodium chloride was added to the solution all the silver (present at `AgNO_(3)`) was precipitated as silver chloride. The weight of the precipitated silver chloride was `14.35g`. Calculate the percentage of silver in the coin. : `4.8%`, `95.2%`, `90%`, `80%`

Options

A. `4.8%`
B. `95.2% `
C. `90% `
D. `80% `

Answer

B

Explanation

`Ag + HNO _(3) to Ag NO _(3)`
`Ag NO _(3) + aNa Cl to Na NO _(3) + Ag Cl`
Mole of Ag in coin = mole of Ag in AgCl
`a = (14. 35)/(143.5) = 0.1 `mole
Mass of A g in coin `= 0.1 xx 108 = 10.8 g therefore %` silver in coin `= (10.8)/(11.34) xx 100% = 95.2 %`