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Multiple choice chemistry basic analytical techniques partition coefficients solvent extraction separation methods

A vendor sells white powdered salt mixed with white powdered stone. The knowledge of which property will help you detect this malpractice?

  1. Ductility

  2. Opacity

  3. Density

  4. Solubility
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The purity of the solid salt sample can be anaylsed simply by checking its solubility in proper solvent,

choose a proper solvent and add a pinch of compound to it, if the compound is completely soluble that means compound is pure.

Multiple choice chemistry basic analytical techniques partition coefficients solvent extraction separation methods

In a separating funnel, one phase is ______ and other phase is :              .

  1. Aqueous phase, organic phase

  2. Aqueous phase, inorganic phase

  3. Inorganic phase, organic phase

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

A separating funnel is used for the separation of components of a mixture between two immiscible liquid phases. One phase is the aqueous phase and the other phase is an organic solvent. This separation is based on the differences in the densities of the liquids. The liquid having more density forms the lower layer and the liquid having less density forms the upper layer.

Multiple choice chemistry basic analytical techniques partition coefficients solvent extraction separation methods

We sprinkle water in a dirty room before sweeping because:

  1. water makes sweeping easier

  2. water repels dust particles

  3. water coagulates the dust particles

  4. sprinkling water is fashionable
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Water acts as a binding agent for dust particles. When sprinkled, it increases the mass of the dust particles, causing them to coagulate and settle, which prevents them from becoming airborne during sweeping.

Multiple choice chemistry basic analytical techniques partition coefficients solvent extraction separation methods

Mixture of ${\text{Al}}{\left( {{\text{OH}}} \right) _3}\,\,{\text{and}}\,\,{\text{Fe}}{\left( {{\text{OH}}} \right) _3}$ can be separated by

  1. ${\text{HCl}}\,$
  2. ${\text{N}}{{\text{H}} _{\text{4}}}{\text{OH}}\,$
  3. ${\text{NaOH}}$
  4. ${\text{HN}}{{\text{O}} _{\text{3}}}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Aluminum hydroxide is amphoteric and dissolves in strong acids like HCl, whereas ferric hydroxide is basic and also dissolves in strong acids. However, in the context of qualitative analysis, HCl is the standard reagent used to dissolve these hydroxides to separate them from other insoluble residues or to bring them into solution for further testing.

Multiple choice chemistry basic analytical techniques partition coefficients solvent extraction separation methods

Separation of $CCl 4$ from $CS _2$ can be carried out by ______ method.

  1. fractional distillation

  2. separating funnel

  3. crystallization

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

Separation of $C{Cl} _{4}$ from $C{S} _{2}$ can be carried out by careful distillation in presence of inert gas stream thus can be carried out by separating funnel method.


Multiple choice chemistry basic analytical techniques partition coefficients solvent extraction separation methods

Two immiscible liquids are separated by?

  1. Separating funnel

  2. Fractional distillation

  3. Chromatography

  4. Sublimation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Separating immiscible liquids is done simply using a separating funnel. The two liquids are put into the funnel and are left for a short time to settle out and form two layers. The tap of the funnel is opened and the bottom liquid is allowed to run. The two liquids are now separate.

Multiple choice chemistry basic analytical techniques partition coefficients solvent extraction separation methods

Name a technique used to separate : Petrol and water

  1. distillation

  2. separating funnel

  3. sublimation

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

Use a separating funnel since the petrol floats above the water.Just let the mixture stand. Petrol and water are not soluble, so they will eventually separate. Since the petrol is lighter than the water, it will form a layer on top, and may be drawn off.Petrol will form at the top of water as it is not as heavy. 

Multiple choice chemistry basic analytical techniques partition coefficients solvent extraction separation methods

Filtration as a method of separation can be used for mixtures that are :

  1. homogeneous and liquid-in-gas mixtures

  2. heterogeneous and liquid-in liquid mixtures

  3. hogeneous and solid-in-liquid mixtures.

  4. heterogeneous and solid-in liquid mixtures
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Filtration is generally used for heterogeneous solution or solution which are partially miscible or immisscible, or in solid liquids phase.