Surface Chemistry Quiz-17

Surface Chemistry Quiz-17

Dear Readers,

The one subject in NEET which is candidates who can easily attain good marks is Chemistry. That's the reason, often, one doesn’t pay notice and choose to compromise it. But if one wants to rank above others, the tip is to be thorough with NEET chemistry concepts. The understanding of reactions and definite basic understanding is what requires major attention in Chemistry but once done it only gets simpler from there. The main focus on the to-do list should be on getting a hang of the NCERT syllabus of NEET chemistry. .

Q1.  Which among the following statements is false?

•   Adsorption may be monolayered or multilayered
•   Particle size of adsorbent will not effect the amount of adsorption
•   Increase of pressure increases the amount of adsorption
•   Increase of temperature may decrease the amount of adsorption

Solution

Q2.  Identify the gas which is readily adsorbed by activated charcoal

•   N₂
•   SO₂
•   H₂
•   O₂

Solution
Easily liquifiable gases (like SO₂,NH₃,CO₂ etc.) are adsorbed up to greater extent than the gases like O₂,H₂,N₂, He etc which liquify with great difficulty.

Q3.  A biological catalyst is

•   The N₂ molecule
•   A biological catalyst is an enzyme.
•   An amino acid
•   An enzyme

Solution
A biological catalyst is an enzyme.

Q4.  Paste is

•   Suspension of solid in a liquid
•   Mechanical dispersion of a solid in liquid
•   Colloidal solution of a solid in solid
•    None of the above

Solution
Paste is suspension of solid in liquid.

Q5. The minimum energy level necessary to permit a reaction to occur is :

•   Internal energy
•   Threshold energy
•   Activation energy
•   Free energy

Solution
  The minimum energy barrier required to be crossed to bring in a chemical change is called threshold energy level.

Q6.  In which process, a catalyst is not used?

•   Deacon’s process
•   Solvay’s process
•   Chamber process
•   Haber’s process

Solution
The catalysts used are CuCl₂ in Deacon’s process, NO in chamber process and Fe in Haber’s process.

Q7. Bleeding due to a cut can be stopped by applying ferric chloride solution in the laboratory. This is due to

•   Coagulation of negatively charged blood particles by Fe³⁺ ions.
•   Coagulation of positively charged blood particles by Cl^-ions.
•   Reaction taking place between ferric ions and the haemoglobin forming a complex
•   Common element, iron, in both FeCl₃ amd haemoglobin

Solution
Bleeding due to cut can be stopped by applying FeCl₃or alum solution. This is due to coagulation of negatively charged colloidal blood particles (albuminoid substance) by positively charged Fe³⁺ ions. These substances are used as styptic (which check the flow of blood).

Q8. Milk is

•   Fat dispersed in water
•   Fat dispersed in milk
•   Fat dispersed in fat
•   Water dispersed in milk

Solution
Milk is an emulsion in which the particles (or globules) of liquid fats are dispersed in water.

Q9. Cloud bursts due to :

•   Attraction towards the electrical charges on the earth
•   Large amount of water present in the cloud
•   Dense clouds are present in the upper atmosphere
•   Mutual discharge of oppositely charged clouds resulting in the coagulation

Solution
Clouds are water-dispersed in air sol carrying + ve and – ve charge on water molecules.

Q10.  The volume of colloidal particles V_c as compared to the volume of solute particles in true solution V_scould be :

•   ∼1
•   ∼10³
•   ∼10²
•   ∼10^-3

Solution