That depends. What kind of change are you talking about? But
Mass<span> through chemical </span>change<span> stays the same as well. Example: burning paper, the ash left behind is not all of the </span>mass<span> of the reactants, Carbon dioxide, and other </span>substances<span> also makeup</span>mass<span> but just is not seen
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The reaction is
2H₂(g) + O₂(g) ---> 2H₂O
Thus as per balanced equation two moles of hydrogen will react with one moles of oxygen.
There is a directly relation between moles and volume. [One mole of each gas occupies 22.4 L of volume at STP]
Thus we can say that two unit volume of hydrogen will react with one unit volume of oxygen
Now as we have started with equal units of volume of both oxygen and hydrogen, half of oxygen will be consumed against complete volume of hydrogen
so the gas which will remain in excess is oxygen
Alkanes can be prepared from carboxylic acid via the removal of carbon dioxide. This process is known as decarboxylation. It produces alkane with a carbon atom lesser than that present in the carboxylic acid.
Answer:
The atmosphere refers to the gaseous envelope of earth, comprised of variable gases with definite proportions. The layers of the earth's atmosphere are as follows-
- Troposphere- This layer starts from the ground and extends up to a height of about 10 km. Here, the temperature decreases with the increasing altitude. All the weather phenomenon takes place in this layer.
- Stratosphere- It starts from 10 km and extends up to a height of about 50 km. Here the temperature increases as the altitude increase. This is because of the presence of the ozone layer that receives the harmful UV radiation emitted from the sun.
- Mesosphere- This layer extends from a height of about 50 km to about 80 km above the earth's surface. Here, again the temperature decreases with the increasing altitude.
- Thermosphere- This layer starts from a height of about 80 km and extends up to about 500 km above the ground surface. In this region again the temperature increases with the increasing elevation.
- Exosphere- This layer ranges from about 500 km to 10,000 km above the earth's surface. Here, the temperature gradually increases with the increasing height.
This variation in temperature occurs because of the certain reason. In the troposphere and the mesosphere, the temperature decreases with height because the pressure and height are inversely proportional to each other. The stratosphere experiences increasing temperature because of the presence of the ozone layer that is responsible for holding the greenhouse gases and the harmful UV radiation. The thermosphere and the exosphere experience high temperatures because of the receiving of the direct sunlight. Due to these above reason, there occurs this temperature change in a unique pattern.
