Determine the amount of `CaCl_(2)` (i = 2.47) dissolved in 2.5 L of water sucjh that its osmotic pressure is 0.75 atm at `27^(@)C`.

Explanation

According to Van't Hoff equation:
`"Osmotic pressure"(pi)=I c R T=(I n_(B)R T)/V `
`i=2.47, V=2.5 L, R=0.0821 L-atm K^(-1) mol^(-1), T=27+273 =300 K, pi=0.75. atm.`
`n_(B)=(piV)/(iRT)=((0.75atm)xx(2.5L))/((2.47)xx(0.0821L atmK^(-1)mol^(-1))xx300 K)=0.0308 mol`
`"Amount of" CaCI_(2) "dissolved= No. of moles "xx"Gram molecular mass of" CaCI_(2)`
`=(0.0308 mol)xx(111.0 g mol^(-1))=3.42 g`