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Multiple choice separation of components of mixtures methods of separation elements, compounds and mixtures chemistry

$\displaystyle { CO } _{ 2 }$ and $\displaystyle CO$ can be separated by :

  1. Chromatography

  2. Solvent extraction

  3. Separation funnel

  4. Magnetic separation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 A gaseous mixture containing CO$ _2$ and CO can be separated by solvent extraction.
The mixture is passed through water.  CO$ _2$ dissolves in water whereas CO does not.

Multiple choice separation of components of mixtures methods of separation elements, compounds and mixtures chemistry

In a mixture of $NH 3$NH3 and $H _2$, _____ Gets liquified under pressure :

  1. $\displaystyle { H } _{ 2 }$
  2. $\displaystyle { NH } _{ 3 }$
  3. $\displaystyle { H } _{ 2 }O$

  4. All of above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In a mixture of NH$ _3$ and H$ _2$, NH$ _3$ gets liquefied under pressure
Liquefaction of gases is the process by which a gas is converted to a liquid. In a mixture of NH$ _3$ and H$ _2$, NH$ _3$ gets liquefied under high pressure and H$ _2$ is left behind.
Note: NH$ _3$ has a higher value of the van der Waal's constant 'a' than $H _{2}$
Hence, NH$ _3$ is more easily liquefiable than H$ _2$.

Multiple choice separation of components of mixtures methods of separation elements, compounds and mixtures chemistry

______ is useful when one gas is easily liquefiable.

  1. Solvent extraction

  2. Crystallisation

  3. Liquefaction

  4. All of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Liquefaction is useful when one gas is easily liquefiable.
Liquefaction of gases is the process by which a gas is converted to a liquid by applying high pressure and low temperature. For example, oxygen normally occurs as a gas. However, by applying high pressure and by reducing the temperature, oxygen can be converted to a liquid.
Note:
In a mixture of NH$ _3$ and H$ _2$, NH$ _3$ gets liquefied under pressure
Liquefaction of gases is the process by which a gas is converted to a liquid. In a mixture of NH$ _3$ and H$ _2$, NH$ _3$ gets liquefied under high pressure and H$ _2$ is left behind.
NH$ _3$ has higher value of the van der Waal's constant 'a' than
Hence, NH$ _3$ is more easily liquefiable than H$ _2$.

Multiple choice separation of components of mixtures methods of separation elements, compounds and mixtures chemistry

Which of the following cannot be used for liquid-liquid separation?

  1. Magnet

  2. Sublimation

  3. Crystallization

  4. All of above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

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.

Multiple choice separation of components of mixtures methods of separation elements, compounds and mixtures chemistry

Gaseous diffusion works on the principle that

  1. Molecules of a lighter isotope would pass through a porous barrier more readily than those of a heavier isotope

  2. Molecules of a heavier isotope would pass through a porous barrier more readily than those of a lighter isotope

  3. Heavier and lighter particles will pass readily through the porous barrier

  4. None of above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

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.

Multiple choice separation of components of mixtures methods of separation elements, compounds and mixtures chemistry

______for the removal of VOCs from air, in recent times have become important due to environmental and economic driving forces.

  1. Liqueafaction

  2. Condensation based gas separations

  3. Solubility-based gas separations

  4. Solidification
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

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.

Multiple choice separation of components of mixtures methods of separation elements, compounds and mixtures chemistry

If a steam-jacket eudiometer with $23ml$ of oxygen and $4ml$ of hydrogen are mixed over mercury, determine how much and which gas would be left as uncombined after the mixture is sparked?

  1. $21$mL $O _2$
  2. $3.0$mL $H _2$
  3. $24$mL $O _2$
  4. $28$mL $O _2$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$\displaystyle  2H _2 + O _2 \rightarrow 2H _2O$
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.