Biology
A glowing matchstick starts burning in the presence of :
- Carbon dioxide gas
- Nitrogen gas
- Carbon monoxide gas
- Oxygen gas
Answer
Oxygen gas
Reason — A glowing matchstick starts burning in the presence of oxygen gas.
Carbon dioxide does not support combustion. In fact, it is used to extinguish fires. Nitrogen is largely inert and does not support burning. Carbon monoxide is a combustible gas itself, but it does not support combustion of other substances like oxygen does.
Related Questions
Which of the following is an immediate product of photosynthesis ?
- Glucose
- Starch
- Sucrose
- Cellulose
Which of the following is an end product of anaerobic respiration in plants ?
- Ethane
- Ethylene
- Ethanol
- Lactic acid
Which of the following chemicals is used to identify the presence of starch ?
- Lime water
- Potassium hydroxide
- Iodine solution
- Methylated alcohol
Assertion (A): Green plants are autotrophs and they use carbon dioxide and water as raw materials to prepare their own food.
Reason (R): Chlorophyll and sunlight are also essential in the process of photosynthesis but they are not utilized as raw materials.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.