How can we help children understand air pollution? This time, chemistry will be of help. Let’s run a small experiment. Its additional advantage is that we do not need too many supplies.
WE WILL NEED:
Light a match. Observe carefully if there is anything lifting above the fire. Bring the match near the bottom of the glass and keep it there for a moment. Wait until the glass cools down before you move on to the next step of the experiment.
There is a black mark on the bottom of the glass. Rub it with your finger and you will see soot on it. Soot is a substance produced due to incomplete combustion of petroleum, plastic or wood, of which matches are made. These substances contain significant amounts of carbon. A lot of research has confirmed that breathing sooty air can cause respiratory and cardiovascular diseases and neoplasms. And this is just the tip of the iceberg – polluted air is bad for our health.
Yet, the problem is much bigger than just that. When wood, plastic or petroleum products are burnt, certain amount of particles of carbon (C), contained in these materials, is released in the air. They combine with oxygen (O2) to form a gas: carbon dioxide (CO2). This gas is one of the greenhouse gases (i.e. those which warm the atmosphere); in addition, it can remain in the atmosphere for decades. Note that each year, factories and cars emit 20 billion tons of this gas. This gas accumulates in the atmosphere, thus causing temperature on Earth to increase, glaciers to melt, sea levels to rise, and climate to change… This is why polluted air is one of the biggest threats to humanity.
Let us conclude this post with a short TED-ed video about smog.