What is the effect of temperature on solubility of gas in a liquid?
Explain refining of nickel of Mond process.
State Kohlrausch's law of independent migration of ions.
Silver crystallises in F.C.C. (face-centred cubic crystal) structure. The edge length of the unit cell is found to be 408.7 pm. Calculate density of the unit cell.
[Given : Molar mass of silver is `108"g mol"^(-1)`]

Explanation

The solubility of gas in a liquid decreases with increase in temperature.
Mond process : Nickel is refined by this technique. In this method nickel is heated in a steam of carbon monoxide to form volatile nickel carbonyl `Ni(CO)_(4)`.
The carbonyl vapour when subjected to still higher temperature `(450-470 k)` undergoes thermal decomposition giving pure nickel.
`underset("Impure")(Ni+)4CO overset(330-350 K)(rarr) underset("Nickel carbonyl")(Ni(CO)_(4)) overset(450-470 K)(rarr) underset("Pure")(Ni+)4CO`
Kohlrausch law : The law states that at infinite dilution, each ion migrates independently of its coion and makes its own contribution to the total molar conductivity of an electrolyte, irrespective of the nature of other ion with which it is associated.
Mathematically, this law of independent migration of ions is represented as :
`Lambda_(m)^(0)=lambda_(+)^(0)+lambda_(-)^(0)`
Where, `Lambda_(m)^(0)` is the molar conductivity of the electrolyte at infinite dilution while `lambda_(+)^(0)` and `lambda_(-)^(0)` are the molar ionic conductivities of the cation and anion respectively at infinite dilution.
Given : No. of atom (Z) in f.c.c. `=4`
Edge length `(a)=408.7` pm
`=408.7xx10^(-10) cm`
Molar mass of silver `=108 g mol^(-1)`
Avogadro's number `(N_(0))=6.022xx10^(23)`
To find : Density `(rho)=?`
Formula used :
`rho=(ZxxM)/(a^(3)xxN_(0))`
`rho=(4xx108)/((408.7xx10^(-10))^(3)xx6.022xx10^(23))`
`rho=(4xx108xx10^(7))/((408.7)^(3)xx6.022)`
`rho=10.50 g/cm^(3)`