The Dhaka Times Desk Both oxygen and carbon-dioxide are important for our survival. We are constantly taking in oxygen and excreting carbon dioxide. Today we will test and learn which of oxygen and carbon-dioxide is fire's friend and which is its enemy.
Both oxygen and carbon-dioxide are important for our survival. We are constantly taking in oxygen and excreting carbon dioxide. Fire has friends just like we have friends. A friend's job is to help another friend. May he easily expand his path. The same is true of the friend of fire. Science gives us some special knowledge from which we can learn a lot. I also get a lot of joy. Today we will learn which of oxygen and carbon dioxide is fire's friend and which is its enemy. So let's learn the fun test.
To do this test you will first need-
1. Two small candles
2. a glass
3. An empty bottle of 250ml size
4. Baking soda
5. Vinegar
Test 1:
First light two candles and place them on the table. When both candles start to burn well, cover one candle over the glass jar. Note, the candle covered with glass slowly went out after burning for a while. But the candle outside burns effortlessly.
Explanation: When the candle is covered with glass, oxygen is no longer able to enter the glass. So the fire went out as the oxygen in the glass ran out. Because fire cannot burn without oxygen. And the outer candle burns effortlessly with oxygen from the air. Then we got a friend of fire. So the friend of fire is oxygen.
Test 2:
Now we will check who is the enemy of fire?
First, light a candle. Now pour 3-4 teaspoons of baking soda into the empty bottle. Then pour vinegar equal to the amount of baking soda in the bottle. Shake it up a bit. Note that the vinegar and baking soda in the bottle are reacting to produce carbon dioxide. Now you gently tilt the bottle (like pouring water) over the candle flame. Note that the fire is extinguished immediately. How did it happen?
Explanation: When the bottle is tilted over the flame, the carbon-dioxide produced in the bottle falls on the flame. And because carbon-dioxide removes oxygen from around the fire, the fire is extinguished due to lack of oxygen. Many of us see red cylinders attached to the walls in various institutions and fire extinguishers are written on them. This cylinder mainly contains carbon dioxide. If there is a fire somewhere, the fire is extinguished by throwing carbon dioxide on it in the initial stage. And this is why carbon-dioxide is called the enemy of fire.
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