Hydrogen and its compounds MCQs Part 21

Hydrogen And Its Compounds MCQ

MCQ-1.  Hydrogen from HCI can be prepared from :

  P
  Mg
  Hg
  Cu

MCQ-2.  Commercial hydrogen is obtained from :

  Producer gas
  Marsh gas
  Oil gas
  Coal gas

MCQ-3.  Oxygen is used to purify water since it :

  absorbs harmful UV radiations
  is reducing
  is paramagentic
  destroys viruses and bacteria

MCQ-4.  How many neutrons are there in protium ? :

  3
  1
  2
  0

MCQ-5.  Which of the following is more stable ? :

  Para hydrogen
  Both are equal
  Can not be said
  Ortho hydrogen

MCQ-6.  Which one is not an isotope of hydrogen ? :

  Ortho hydrogen
  Deuterium
  Tritium
  None of the above

MCQ-7.  Pure water can be obtained from sea water by :

  Reverse osmosis
  Plasmolysis
  Sedimentation
  Centrifugation

MCQ-8.  Which one of the following metals will not reduce water? :

  Fe
  Cu
  Li
  Ca

MCQ-9.  The maximum possible number of hydrogen bonds a water molecule can from is :

  3
  2
  4
  1

MCQ-10.  In the structure of ice , each oxygen atom is surrounded by four other oxygen atoms :

  Octahedrally
  In a square planar manner
  Tetrahedrally
  None of the above

MCQ-11.  The alum used for purifying water is :

  Chrome alum
  Ammonium alum
  Ferric alum
  Potash alum

MCQ-12.  The process used for the removal of hardness of water is :

  Serpeck
  Hoope
  Calgon
  Baeyer

MCQ-13.  The exhausted permutit is generally regenerated by percolating through it a solution of :

  Calcium chloride
  Magnesium chloride
  Potassium chloride
  Sodium chloride

MCQ-14.  When sulphur trioxide is heated with heavey water the products are :

  Deuterium sulphuric acid
  Deuterium and sulphuric acid
  Deutero-sulphuric acid
  None of the above

MCQ-15.  Heavy water is used as :

  Detergent
  Drinking water
  A moderator
  Washing water

MCQ-16.  An aqueous solution of hydrogen peroxide is :

  Neutral
  Weakly acidic
  Strongly acidic
  Alkaline

MCQ-17.  Hydrogen peroxide is used as :

  An acid only
  An oxidant only
  A reductant only
  An oxidant , a reductant and an acid

MCQ-18.  The Low density of ice compared to water is due to :

  Dipole- dipole interactions
  Induced dipole- induced dipole interactions
  Hydrogen bonding interactions
  Dipole - induced dipole interactions

MCQ-19.  Which can't displace hydrogen from the compounds ? :

  Zn
  Fe
  Hg
  None of the above

MCQ-20.  The property of hydrogen which distinguishes it from alkali metals is :

  Its affinity for non-metals
  Its non-metallic character
  Its electropositive character
  Its reducing character

General Organic Chemistry MCQs Part 20

General Organic Chemistry MCQs

MCQ-1.  The shortest C - C bond distance is found in :

  Ethane
  Benzene
  Diamond
  Acetylene

MCQ-2.  Which of the following forces is strongest among the following ? :

  Dipole-dipole forces
  H-Bonding
  All equal
  Vander Waals forces

MCQ-3.  Which of the following free radicals is most stable ? :

  Methyl
  Secondary
  Tertiary
  Primary

MCQ-4.  Which of the following is an example of elimination reaction ? :

  Dehydration of ethanol
  Chlorination of methane
  Hydroxylation of ethylene
  Nitration of benzene

MCQ-5.  Acetaldehyde is the rearrangement product of :

  Vinyl alcohol
  Allyl alcohol
  Methyl alcohol
  All are correct

MCQ-6.  The least number of carbon atoms in alkane forming isomers is :

  3
  1
  4
  2

MCQ-7.  Diethyl ether is associated with which one of these isomers ? :

  Steroisomerism
  Methyl propionate
  Butanoic acid
  None

MCQ-8.  Number of primary and tertiary hydrogen atoms present neopentane are respectively :

  6,6
  12,0
  9,3
  5,7

MCQ-9.  Glucose and fructose are :

  Position isomers
  functional isomers
  optical isomers
  chain isomers

MCQ-10.  The least number of carbon atoms for an alkane to show stereoisomerism is :

  5
  3
  2
  4

Science Quiz: Purification and analysis of organic compounds MCQ Part 19

Purification and analysis of organic compounds MCQ

These are some of the random multiple question answers from Purification and analysis of organic compounds...

1. Anthracene is purified by which method :

  Distillation
  Sublimation
  Filtration
  Crystallisation

2.  A bottle containing two immiscible liquids. These liquids may be separated by using a :

  Separating funnel
  Vacuum distillation
  Fractionating coloumn
  Steam distillation

3.  When Lamery proposed his classifications of substances in the year 1675 the substance not know among the following was :

  Wine
  Iron
  Cane sugar
  Penicillin

4.  In laboratory, first organic compound was synthesized by_________  :

  Hennel
  Wohler
  Liebig
  Kekule

5. A mixture of oil and water is separated by which method:

  Sublimation
  Filtration
  Using separating funnel
  Fractional distillation

6. First organic compound to be synthesised was ________:

  Cane sugar
  Acetic acid
  Urea
  Methane

7.  Separation of two substance by fractional crytallisation depends upon their differences in the__________ :

  Crystalline shape
  Solubility
  Volatility
  Densities

8. Impure naphthalene is purified by which method  :

  Sublimation
  Fractional distillation
  Soxhlet extraction
  Fractional crystallization

9.  Which of the following not sublimate :

  Chlorine
  Bebzoic acid
  Camphor
  Naphthalene

10. Aniline is purified by which method:

  Extraction with a solvent
  Vacuum distillation
  Simple distillation
  Steam distillation

Class 11 Chapter 6 - Thermodynamics

Class 11 Chapter 6: Thermodynamics

System:

            A system is that part of universe in which we made observations is called system.

Surroundings:

            All remaining part of the universe, other than system is called surroundings.

Universe = System + Surroundings

Types of System:

            The system is classified on the basis of movement of energy and matter inside or outside the system. I.e. open system, closed system and isolated system.

     1.     Open System:

A system in which exchange of matter and energy between the system and surroundings take place, is called open system.

Example:- Reaction in open beaker.

     2.     Closed System:

A system in which exchange of energy between the system and surroundings take place but there is no exchange of matter between the system and surroundings takes place, is called closed system.

Example:- Reaction in closed conducting vessel of steel.

     3.     Isolated System:

A system, in which no exchange of matter and energy between the system and surroundings take place, is called isolated system.

Example:- Reaction in isolated vessel like thermos flask.

The state of the system

            In chemistry, the state of thermodynamic system is described by the measurable or macroscopic i.e. bulk properties of the thermodynamic system.

To learn better, if someone asks, how we can describe the state of a gas?

So to answer this question, we describe the state of a gas by getting information about pressure (p), volume (V), temperature (T) and amount (n) etc. of gas.

So, these variables i.e. p, V, T are known as state variables or state functions.

Why these variables (p, V, T) are called state variables or state functions?

These variables are called state variables or state functions because their values depends only on the state of the system and do not depend on how they are reached on that point.

Internal Energy

            Sum of all energies (like chemical, electrical, mechanical etc.) of the system is called internal energy (U) of the system.

Now question is when internal energy of the system changes?

Internal energy of the system changes when,

·        Heat passes into or heat passes out of the system.

·        Work is done on the system or work is done by the system.

·        Matter enters the system or matter leaves the system.

     i.       Work

Before learning about effect of work on internal energy we first understand what is Adiabatic system.

Adiabatic system

            Adiabatic system is a system which does not allow transfer of heat through its boundary; means heat can not enters or leave the system.

Work on adiabatic system

            If 1kJ mechanical work done (case 1) on the system and 1kJ electrical work done (case 2) on the system than change in temperature is same in bath cases.

So, amount of work done on the system produces the same change of state no matter how this work was done.

So,

            ∆U = U₂ – U₁ = W_ad

Where,

            U = internal energy

            U₂ = internal energy at state 2 (final state)

U₁ = internal energy at state 1 (initial state)

W_ad = adiabatic work

Sign of W_ad

a.     If W_ad is positive, then work is done on the system.

b.     If W_ad is negative, then work is done by the system.

      ii.     Heat

What is heat?

The exchange of energy due to difference in temperature is called heat.

If system allows exchange of heat (conducting walls of the system) then change in internal energy depends on amount of heat transfer between system and surroundings at constant volume when no work is done.

So,

            ∆U = q

Where,

            U = internal energy

            q = heat

            Sign of q

a.     q is positive, if heat is transferred from the surroundings to the system.

b.     q is negative, if heat is transferred from the system to surroundings.

Structure of Atom Class 11 MCQ

Structure of Atom MCQ

These are some of the random multiple question answers from Structure of Atom... 

1. Who discovered anode rays :

 Goldstein
 Rutherford
 J. Stanley
 J. J. Thomson

2. Neutron was discovered by :

 Rutherford
 Chadwick
 Austin

 Langmuir

3. Radioactive isotope of hydrogen has ________ number of neutrons :

 0

 1

 2

 3

4. Cathode rays are deflected by :

 A magnetic field only
 An electric field only

 By Both
 By None

5. Cathode rays have :

 Mass Only
 Charge Only
 Mass and Charge Both
 No Charge and No Mass

6. Mass of atom is mainly constituted by :

 Neutrons and neutrino
 Neutrons and electrons

 Neutrons and protons
 Protons and electrons

7. Ratio of mass of proton and electron is :

 1.8
 1.8x10³

 Infinite
 None of these

8. Atomic number of an element is equal to the number of  :

 Proton

 Electron

 Neutron

 Electron and Proton

9. Size of nucleus is :

 10^-8 m

 10^-10 m

 10^-12 m

10^-15 m

10. Who modifies Bohr’s model :

 Dalton
 Pauli
 Rutherford
 Sommerfeld

Also read Chemistry Notes of this chapter at below link...
11 Class Chapter 2- Structure of Atom