Chapter 2 Element Compound and Chemical Reaction MCQs
Question 1. The enzymes are basically
- Carbohydrates
- Proteins
- Fats
- Minerals
Answer: 2. Proteins
Question 2. The catalyst used to prepare ammonia from nitrogen and hydrogen is
- Vanadium pentoxide
- Iron powder
- Zinc powder
- Molybdenum
Answer: 2. Iron powder
Question 3. The catalyst used to prepare s03 from sO2 and oxygen is
- Vanadium pentoxide
- Hydrogen peroxide
- Manganese dioxide
- Red hot iron
Answer: 2. Hydrogen peroxide
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Question 4. The enzyme pepsin is found in our
- Liver
- Stomach
- Intestine
- Gall bladder
Answer: 2. Stomach
Question 5. Which one is not correct?
- The catalyst influences the rate of reaction but does not participate in the reaction
- There is no universal catalyst which can enhance the rate of all the reactions.
- A suitable catalyst for a specific reaction can only be found by proper experimentation.
- A powdered catalyst is more effective than a solid one due to increased surface area.
Answer: 1. Catalyst influences the rate of reaction but does not participate in the reaction
Question 6. The enzyme invertase
- Converts proteins into smaller amino acids
- Converts sucrose to glucose and fructose
- Decomposes hydrogen peroxide
- Hydrolyses lipid
Answer: 2. Converts sucrose to glucose and fructose
Question 7. When rusting occurs, the weight of iron
- Increases
- Decreases
- Remains unchanged
- None of these
Answer: 1. Increases
Question 8. Potassium permanganate is
- An enzyme
- A reducing agent
- An oxidizing agent
- A corrosive agent
Answer: 3. An oxidizing agent
Question 9. formation of ammonia from nitrogen and hydrogen is
- An exothermic reaction
- An endothermic reaction
- Not influenced by catalyst
- None of these
Answer: 1. An exothermic reaction
Question 10. for rusting of iron
- Moist air is required
- Only water is required
- Only oxygen is required
- Nothing is required
Answer: 1. Moist air is required
Question 11. the activity of a catalyst is enhanced depending upon
- Its volume
- It’s mass
- It’s the surface area
- Its density
Answer: 3. It’s the surface area
Question 12. An example of an inorganic solvent is
- Benzene
- Water
- Toluene
- Kerosene
Answer: 2. Water
Question 13. A catalyst
- Is required in a large amount
- Cannot initiate a reaction
- Cannot influence the rate of a reaction
- Is consumed in the reaction
Answer: 2. Cannot initiate a reaction
Question 14. Reduction involves
- Addition of oxygen or chlorine
- Removal of hydrogen
- De-electronation
- Electronation
Answer: 4. Electronation
Question 15. \(\mathrm{Fe}_2 \mathrm{O}_3+3 \mathrm{C} \rightarrow 2 \mathrm{Fe}+3 \mathrm{CO}\) in this reaction,
- Fe undergoes oxidation and c undergoes reduction
- Both fe and c undergo oxidation
- Both fe and c undergo a reduction
- Fe undergoes reduction and c undergoes oxidation
Answer: 4. Fe undergoes reduction and c undergoes oxidation
Question 16. rusting of iron is an example of
- Oxidation and displacement reaction
- Reduction and combination reaction
- Oxidation and combination reaction
- Reduction and displacement reaction
Answer: 3. Oxidation and combination reaction
Question 17. The same substance which can act both as an oxidant and reductant is
- K2cr207
- H2O2
- Co
- FecI3
Answer: 2. H2O2
Chapter 2 Element Compound And Chemical Reaction Chemical Reaction Match The Columns
Column – A | Column – B |
A. Urease | 1. Converts proteins into smaller amino acids |
B. Pepsin | 2. Hydrolysis of urea |
C. Catalase | 3. Conversion of sucrose into glucose and fructose |
D. Invertase | 4. Decomposition of H2O2 |
Answer: A-2,B-1,C-4,D-3
Column – A | Column – B |
A. Oxidation | 1. Gain of electron |
B. Reduction | 2. Negative catalyst in the decomposition of H2O2 |
C. Rusting | 3. Loss of electrons |
D. H3PO4 | 4. Oxidation |
Answer: A-3,B-1,C-4,D-2
Chapter 2 Element Compound And Chemical Reaction Chemical Reaction Fill In The Blanks
Question 1. Combustion of methane is an __________ reaction.
Answer: Oxidation
Question 2. In a redox reaction, oxidising agent (or oxidant) is __________.
Answer: Reduced
Question 3. In a redox reaction, oxidising agent (or oxidant) accepts __________.
Answer: Electrons
Question 4. In a redox reaction, a reducing agent (or reductant) __________ electron (s).
Answer: Losses
Question 5. In a redox reaction, a reducing agent (reductant) is __________ (i.e., converted to oxidized species).
Answer: Oxidized
Question 6. Increasing the temperature increases the __________ energy of the molecules.
Answer: Kinetic
Question 7. “Like dissolves __________”.
Answer: Like
Question 8. An article made of iron is coated with a thin __________
Answer: Electroplating
Question 9. The enzyme __________ decomposes hydrogen peroxide (H2O2) to water and oxygen.
Answer: Catalase
Question 10. Arhar daal and watermelon seeds contain the enzyme __________
Answer: Urease
Question 11. The enzyme, __________ is found in the fresh potato.
Answer: Catalase
Question 12. __________ reaction is a chemical reaction in which chlorine is added.
Answer: Oxidation
Question 13. __________ is a chemical reaction in which the addition of hydrogen occurs with an element or a compound.
Answer: Reduction
Question 14. Oxidation is defined as a chemical reaction involving __________ of electrons from an atom or ion.
Answer: Loss
Question 15. Reduction is a chemical reaction involving __________ of an electron by an atom or ion.
Answer: Gain
Question 16. __________ acts as a catalyst in the decomposition of H2O2 into Oxygen and water
Answer: MnO2
Chapter 2 Element Compound And Chemical Reaction Chemical Reaction Identify As ‘True Or False
Question 1. If the temperature is increased, the kinetic energy of the molecules increases.
Answer: True
Question 2. Rusting is basically a reduction of iron.
Answer: False
Question 3. When an atom loses an electron(s), it is oxidized.
Answer: True
Question 4. Water acts as a solvent in many chemical reactions.
Answer: True
Question 5. The choice of catalyst for a particular chemical reaction can only be determined by performing the experiments only. It cannot be predicted.
Answer: True
Question 6. In the case of a solid catalyst, when it is crushed, its surface area decreases.
Answer: False
Question 7. As the surface area of a solid catalyst increases, the rate of the reaction decreases.
Answer: False
Question 8. The combustion of fossil fuel is an example of an oxidation reaction.
Answer: True
Question 9. Photosynthesis requires sunlight.
Answer: True
Question 10. Oxidation and reduction cannot occur simultaneously in a chemical reaction.
Answer: False
Question 11. \( \mathrm{Cu}^{2+}+2 \mathrm{e} \rightarrow \mathrm{Cu} .\) This is an oxidation reaction.
Answer: False
Question 12. Enzymes are biological molecules that act as catalysts and help complex reactions to occur.
Answer: True
Question 13. The enzymes are basically proteins.
Answer: True
Question 14. Trypsin is found in our intestines.
Answer: True
Question 15. Pepsin converts proteins into smaller amino acids in our stomach.
Answer: True
Question 16. An oxidation reaction is a chemical reaction in which chlorine is added.
Answer: True
Question 17. In a redox reaction, oxidising agent (or oxidant) accepts electron(s) and is reduced (i.e., converted to reduced species).
Answer: True
Question 18. In a redox reaction, a reducing agent (or reductant) loses an electron(s) and is oxidized (i.e., converted to oxidized species).
Answer: True
Question 19. When metallic iron is exposed to moist air, rusting of iron occurs.
Answer: True
Question 20. Endothermic reactions are responsible for explosive reactions.
Answer: False