Tag: methods of separation

Vapour Density for Sulphur dioxide is 32, for Nitrogen is 14, Carbon monoxide is 14 and ammonia is 8.5 .

Vapour density for ammonia is 8.5 while for chlorine is 35.5, HCl is 18.25 and oxygen is 16.

Magnetic separation and sublimation can be used to separate solid from solid. Crystallization is used to recover solid from liquid. Hence, none of the above methods is used for separation of liquid from liquid.

Gaseous diffusion works on the principle that molecules of a lighter isotope would pass through a porous barrier more readily than those of a heavier isotope.

Solubility-based gas separations for applications such as the removal of VOCs from air, in recent times have become important due to environmental and economic driving forces.The main objective is to obtain membranes that exhibit high permeability and high selectivity for the heavier species over the light gases.

$\displaystyle  2H _2 + O _2 \rightarrow 2H _2O$
2 moles of hydrogen will react with 1 mole of oxygen.
Volume is directly proportional to the number of moles.
4 ml of hydrogen will react with $\displaystyle  \dfrac {4 \times 1}{2}= 2$  ml of oxygen.
$\displaystyle  23-2 = 21 ml$  of oxygen will be left uncombined.

$\displaystyle  2H _2 + O _2 \rightarrow 2H _2O$
2 moles of hydrogen will react with 1 mole of oxygen to form 2 moles of water.
Volume is directly proportional to the number of moles.
4 ml of hydrogen will react with $\displaystyle  \dfrac {4 \times 1}{2}= 2$  ml of oxygen to form 4 ml of water.
$\displaystyle  23-2 = 21 ml$  of oxygen will be left uncombined.
Thus, after the mixture was sparked, 21 ml oxygen and 4 ml water are present.
Total volume of the gas after the mixture was sparked $\displaystyle  = 21 + 4 = 25 $ ml.

Gaseous diffusion is a technology used to produce enriched uranium by forcing gaseous uranium hexafluoride through semipermeable membranes. This produces a slight separation between the molecules containing uranium-235 and uranium-238. By use of a large cascade of many stages, high separations can be achieved. 

Distillation is a process of separating the component or substances from a liquid mixture by selective evaporation and condensation. Distillation may result in essentially complete separation (nearly pure components), or it may be a partial separation that increases the concentration of selected components of the mixture.

A cheque was suspected to be forged. Chromatography could be used to compare the various pigments in the different inks.  Here, different inks will have different affinity for  stationary phase  and solvent (mobile phase).