Question

________________ is the second layer of the atmosphere which reaches 48km above the Earth’s surface.

Answer 1

Hint: Atmosphere is the protective layer of gases that acts as a blanket around the Earth’s surface. Earth’s atmosphere is a mixture of various gases and particles which react with each other sometimes under normal conditions and sometimes due to the presence of certain elements. It consists of six different layers at different levels.

Complete answer:
We know that Earth’s atmosphere is a protective layer of a mixture of various gases and particles. These gases react with each other under normal conditions and also in the presence of various particles or elements. Earth’s atmosphere contains 78% nitrogen, 21% oxygen and 1% other gases. These other gases are carbon dioxide, argon and various others. Oxygen is the most reactive amongst them.
Atmosphere consists of six different layers at different temperature levels. These are namely – the troposphere, stratosphere, mesosphere, thermosphere, ionosphere and exosphere. The Stratosphere is the second layer of the atmosphere which reaches 48km above the Earth’s surface. It comes after the troposphere. This is the layer where the ozone layer is found. The ozone layer in the atmosphere is a protective layer against the harmful ultraviolet rays from the Sun as it absorbs most of the UV radiations from the Sun. The Stratosphere covers about 24% of the total Earth’s atmosphere. We cannot breathe in this layer as it consists of the toxic thin air but it supports bacterial life and certain species of birds can also fly in the lower levels of this layer. Also airplanes fly in this layer as it is dry and has very little water vapour and clouds which help the airplanes to fly without much turbulence.

Thus, the answer to the question is The Stratosphere.

Note:
The chlorofluorocarbons CFCs are emitted from refrigerants and air conditioners into the atmosphere where they deplete the ozone layer which protects us from the cancer-causing UV rays from the Sun. This depletion or thinning of the ozone layer is known as ozone hole which is very harmful. But reports have stated that the layer is recovering at a good rate.