Put your knowledge to the test with MCQ on Chemical Reactions and Equations!
MCQ on Chemical Reactions and Equations
1. Which of the following best defines a chemical reaction?
a) Change in color or state
b) Formation of a new substance with new properties
c) Change in temperature
d) No change in physical appearance
Answer: b) Formation of a new substance with new properties
2. What observation can help determine a chemical reaction?
a) Change in temperature
b) Change in color
c) Formation of a precipitate
d) All of the above
Answer: d) All of the above
3. What is the law of conservation of mass?
a) Matter cannot be created or destroyed
b) Mass can be created or destroyed in a chemical reaction
c) Mass remains constant in a chemical reaction
d) Mass increases in a chemical reaction
Answer: a) Matter cannot be created or destroyed
4. Which of the following types of reactions requires heat to carry out?
a) Decomposition
b) Precipitation
c) Combination
d) Displacement
Answer: a) Decomposition
MCQs on Environmental Studies
5. What type of reaction occurs when a more reactive element displaces a less reactive element from its compound?
a) Combination
b) Decomposition
c) Displacement
d) Precipitation
Answer: c) Displacement
6. What is the main characteristic of an exothermic reaction?
a) Heat is absorbed during the reaction
b) Heat is evolved during the reaction
c) It requires light to occur
d) It is a slow reaction
Answer: b) Heat is evolved during the reaction
7. Which of the following is a method to prevent rancidity in food?
a) Use of air-tight containers
b) Refrigeration
c) Addition of antioxidants or preservatives
d) All of the above
Answer: d) All of the above
8. What is the term for a reaction where two compounds exchange ions to form new products?
a) Combination reaction
b) Decomposition reaction
c) Displacement reaction
d) Double displacement reaction
Answer: d) Double displacement reaction
9. Which of the following statements about oxidation and reduction is correct?
a) Oxidation involves gaining electrons
b) Reduction involves losing electrons
c) Oxidation involves losing electrons
d) Reduction involves gaining protons
Answer: c) Oxidation involves losing electrons
10. Which of the following is an example of an endothermic reaction?
a) Combustion of wood
b) Dissolution of salt in water
c) Decomposition of water into hydrogen and oxygen
d) Formation of rust on iron
Answer: c) Decomposition of water into hydrogen and oxygen