Chemistry Solved Questions and Answers Set 20

Q.1:- Milk is a ?

  1. Mixture
  2. Element
  3. Metal
  4. None of these

Q.2:- Which one of the following mixture is homogeneous ?

  1. Starch and Sugar
  2. Methanol and Water
  3. Calcium Carbonate and Calcium Bicarbonate
  4. Graphite and Charcoal

Q.3:- Positive ions are formed from neutral atoms by loss of ?

  1. Neutrons
  2. Protons
  3. Nuclear Charge
  4. Electrons

Q.4:- Wave length of X-rays is of the order of ?

  1. 1 mm
  2. 1 cm
  3. 1 micron
  4. 1 angstrom

Q.5:- The atoms of the elements which have same number of neutrons are called ?

  1. Isobars
  2. Isotopes
  3. Isotones
  4. None

Q.6:- Group displacement law was given by ?

  1. Bacquerel
  2. Rutherford
  3. Mendeleev
  4. Soddy and Fajan

Q.7:- Which one of the following is not radioactive ?

  1. Astanine
  2. Francium
  3. Tritium
  4. Zirconium

Q.8:- Of the following elements, which one has the same oxidation state in all of its compounds ?

  1. Hydrogen
  2. Fluorine
  3. Carbon
  4. Oxygen
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Q.9:- The oxidation number of S in Na2S4O6 is ?

  1. +0.5
  2. 5
  3. +4
  4. +6

Q.10:- The pH scale had been given by ?

  1. Arrhenius
  2. Bronsted
  3. Sornsen
  4. Lewis

Q.11:- Which of the following gases will have the highest rate of diffusion ?

  1. O2
  2. CO2
  3. NH3
  4. N2

Q.12:- Enzymes are ?

  1. Carbohydrates
  2. Acids
  3. Protein
  4. None

Q.13:- During the evaporation of a liquid ?

  1. The enthalpy decreases
  2. The enthalpy increases
  3. The enthalpy remains unchanged
  4. The internal energy decreases

Q.14:- In which of the following, the entropy decreases ?

  1. Crystallization of sucrose from solution
  2. Rusting of Iron
  3. Melting of Ice
  4. Vaporization of camphor

Q.15:- The vertical lines in modern periodic table are called ?

  1. Period
  2. Group
  3. Non-Metal
  4. None

Q.16:- The first attempt to classify elements was made by ?

  1. Mendeleev
  2. Newland
  3. Lothar-Meyer
  4. Dobereiner
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Q.17:- A mixture of Benzene and Toluene forms ?

  1. An ideal solution
  2. Non-ideal solution
  3. Suspension
  4. Emulsion

Q.18:- At high altitudes the boiling point of water lowers because ?

  1. Atmospheric pressure is low
  2. Atmospheric pressure is high
  3. Temperature is low
  4. None of these

Q.19:- The device which converts chemical energy of fuels directly into electrical energy is ?

  1. Concentration cell
  2. Galvanic cell
  3. Fuel cell
  4. Both (B) and (C)

Q.20:- The process of separating a crystalloid from a colloid by filtration is called ?

  1. Emulsification
  2. Dialysis
  3. Coagulation
  4. Peptization

Q.21:- Butter is a colloid formed when ?

  1. Fat is dispersed in water
  2. Fat globules are dispersed in water
  3. Water is dispersed in fat
  4. Suspension of casein in water

Q.22:- Muddy water is treated with Alum in purification process, it is termed as ?

  1. Adsorption
  2. Emulsification
  3. Absorption
  4. Coagulation
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Q.23:- Fog is an example of colloidal system of ?

  1. Liquid in a gas
  2. Gas in a liquid
  3. Gas in a solid
  4. Solid in a liquid

Q.24:- The enzyme ptyalin used for digestion of food is present in ?

  1. Saliva
  2. Blood
  3. Intestine
  4. Adrenal Gland

Q.25:- Heating of a ore below its melting point in the absence of air is known as ?

  1. Roasting
  2. Smelting
  3. Refining
  4. Calcination