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Multiple choice chemistry separation of substances classification of mixtures mixtures: examples and properties types of solutions

In a mixture, constituents exhibit:

  1. similar properties

  2. only those properties which are characteristic to the mixture.

  3. their own properties

  4. no properties
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Impure substances are commonly called mixtures. A mixture is a material containing two or more elements or compounds that are in close contact and are mixed in any proportion. The constituents of mixtures exhibit their individual properties. These constituents can be separated by physical means.

Multiple choice chemistry separation of substances classification of mixtures mixtures: examples and properties types of solutions

The alloy bronze contains Copper and Tin. This is a:

  1. homogeneous mixture

  2. heterogeneous mixture

  3. solid solution of two immiscible metals

  4. both A and B
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Generally, an alloy is a mixture of two or more elements, at least one of which is a metal, and which exhibits metallic bonding characteristics. It may be either homogeneous (eg a solid solution; i.e. single phase; e.g brass) or heterogeneous ( a mixture of metallic phases e. g. Steel— the iron/carbon system) 

Multiple choice chemistry separation of substances classification of mixtures mixtures: examples and properties types of solutions

Column II gives method to separate phases mentioned in column I. Match them and select the correct answer from the codes given below.

Column I Column II
(a) Miscible liquids (p) Distillation
(b) Immiscible liquids (q) Crystallization
(c) Pure copper sulphate  from an impure sample (r) Sublimation
(d) Salt and ammonium chloride (s) Separating funnel

  1. (a) - (q), (b) - (s), (c) - (p), (d) - (r)

  2. (a) - (p), (b) - (s), (c) - (q), (d) - (r)

  3. (a) - (r), (b) - (s), (c) - (p), (d) - (q)

  4. (a) - (r), (b) - (s), (c) - (q), (d) - (p)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sublimation is the transition of a substance directly from the solid to the gas phase without passing through the intermediate liquid phase.
Salt and ammonium chloride can be separated using this.
Crystallization is also a chemical solid-liquid separation technique, in which mass transfer of a solute from the liquid solution to a pure solid crystalline phase occurs.
Pure copper sulphate from an impure sample.
Distillation is a process of separating the component 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 separating funnel is a glass funnel with a tap at the bottom. A separating funnel is a separation technique that is used for two liquids that do not dissolve in each other.

Multiple choice chemistry separation of substances classification of mixtures mixtures: examples and properties types of solutions

A gray solid when heated vaporised to form pure white crystals on the cooler parts of the test tube and heavily, black solid as the residue. It is likely that the original solid is :

  1. an element

  2. a metal

  3. a pure compound

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

Heating is a physical means to separate a mixture of two substances which are not chemically together as in a compound so they are separated by heating.

Multiple choice chemistry separation of substances classification of mixtures mixtures: examples and properties types of solutions

A _____ is a mixture of two or more substances in a single phase.

  1. Element

  2. Compound

  3. Solution

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

A solution is a mixture of two or more substances in a single phase. At least two substances must be mixed in order to have a solution. Since solutions are mixtures, their compositions may vary over a very wide range. The concentrations may be expressed using a variety of measures.

Multiple choice chemistry separation of substances classification of mixtures mixtures: examples and properties types of solutions

Which of the following statement is incorrect about mixtures?

  1. A mixture contains two or more substances

  2. Particles in mixtures are of more than one kind

  3. Compounds or elements in a mixture is mixed in any proportion by mass

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

A mixture is a combination of two or more materials, compounds or elements where there is no chemical combination or reaction.

Here materials can be anything for example: compounds, elements etc.