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

Mixtures on separation can give ____________.

  1. elements

  2. compounds

  3. both elements and compounds

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

Mixtures can be obtained by a combination of elements and compounds. Thus when they are separated, it can give both elements and compounds, depending upon the constituents of a mixture.
Example: Air is the mixture of various gases. It on separation gives oxygen, nitrogen, carbon dioxide, etc. 

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

The amountof $H _2S$ required to precipitate $1.69$g $BaS$ from $BaCl _2$ solution is : 

  1. $3.4g$
  2. $0.24g$
  3. $0.34g$
  4. $0.17g$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$BaCl _2+H _2S\longrightarrow BaS+2HCl$
                                  $1.69$ $g$
For $1$ $mole$ of $H _2S$ produce $1$ $mole$ of $BaS$
So, $1$ $mole$ $H _2S\longrightarrow 1$ $mole$ $BaS$
            $34$ $g$                      $169$ $g$
                      $(x)\longleftarrow 1.69$ $g$
$\implies x=\cfrac {1.69\times 34}{169}=0.34$ $g$
Amount of $H _2S$ needed $=0.34$ $g$

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

$3$ litre of mixture of propane $(C {3}H _{8})$ $ butane $(C{4}H_{10})$ on complete combustion gives $10$ litre $CO_{2}$. Find the composition of mixture.

  1. $C _{3}H _{8}2L$ and $C _{4}H _{10}\ 1L$
  2. $C _{3}H _{8}3L$ and $C _{4}H _{10}\ 0L$
  3. $C _{3}H _{8}\ 1.5L$ and $C _{4}H _{10}\ 1.5L$
  4. $C _{3}H _{8}\ 0L$ and $C _{4}H _{10}\ 3L$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Let x be the volume of propane and y be the volume of butane. We have x + y = 3. The combustion reactions are C3H8 + 5O2 -> 3CO2 + 4H2O and C4H10 + 6.5O2 -> 4CO2 + 5H2O. Thus, 3x + 4y = 10. Solving these equations gives x = 2 and y = 1.

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

An aqueous solution containing $1g$ of urea boils at $100.25^ {o}C$. The aqueous solution containing $3g$ of glucose in the same volume will boil at-

  1. $100.75^ {o}C$
  2. $100.5^ {o}C$
  3. $100^ {o}C$
  4. $100.25^ {o}C$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The boiling point elevation depends on the molality of the solution. Urea (molar mass 60) and glucose (molar mass 180) have different molar masses. 1g urea is 1/60 moles, while 3g glucose is 3/180 = 1/60 moles. Since the number of moles is the same in the same volume, the molality is identical, resulting in the same boiling point elevation.

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

Mixture is a physical combination of two or more pure substances.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mixture, a physical combination of two or more pure substances. A mixture is distinguished from a compound, which is formed by the chemical combination of two or more pure substances in a fixed, definite proportion. 

It should be noted that the components of a mixture retain their own chemical properties and may be present in any proportion.

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

Gunpowder is an example of a__________.

  1. compound

  2. mixture

  3. element

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Gunpowder is an explosive mixture of potassium nitrate, charcoal, and sulphur in ratio 75 : 15: 10 used in time fuses, blasting and fireworks. 
It is obtained by mixing compounds so it is not a compound or an element.
Multiple choice chemistry separation of substances classification of mixtures mixtures: examples and properties types of solutions

A true solution (or simply a solution) is a homogeneous mixture, in which the solute and solvent molecules cannot be distinguished even under a microscope.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A true solution (or simply a solution) is a homogeneous mixture, i.e., in a true solution, the solute and solvent molecules cannot be distinguished even under a microscope because the size of the particle is very small.

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

Which among the following statement(s) is/are true?

  1. Brass is an element

  2. Dry ice is a mixture

  3. Aerated drink, e.g., coca cola is a mixture

  4. Diesel is a mixture
Reveal answer Fill a bubble to check yourself
C,D Correct answer
Explanation

A ) Brass is an alloy made of copper and zinc.
B) Dry ice, sometimes referred to as "cardice" (chiefly British chemists), is the solid form of carbon dioxide, so it is a compound.
C) Aerated drink would be anything that would have fizz (gas) filled in it. For example, your pepsi, coke, thums up, mirinda etc.
D) Diesel is mixture of many hydrocarbons.
Options C & D are correct.