Which of the following best describes the process of photosynthesis?
ABreakdown of glucose to produce energy and CO₂
BConversion of light energy into chemical energy using CO₂ and water
CProduction of glucose without involving chlorophyll
DRelease of oxygen as a waste product only
Correct Answer:
B. Conversion of light energy into chemical energy using CO₂ and water
Explanation:
Photosynthesis is the process by which plants convert light energy into chemical energy in the form of glucose, using carbon dioxide and water. The overall equation is 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂.
Which of the following is an endothermic reaction?
ACombustion of fuel
BMelting of ice
CCondensation of water vapor
DRusting of iron
Correct Answer:
B. Melting of ice
Explanation:
Melting of ice is an endothermic reaction as it requires absorption of heat energy. Combustion and rusting are exothermic reactions that release heat; condensation is also exothermic.