Why can't we see N2 and H2 in color?

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In summary, N2 and H2 gases appear colorless because their electronic states are far apart in energy and they only absorb in the vacuum ultraviolet region. Although emission bands are present in the visible region, they can only be seen through an electric discharge at low pressure.
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Muthumanimaran
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why N2, H2 gas are colourless when visible light scatters it? why can't i see N2 and H2 coloured
 
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Muthumanimaran said:
why N2, H2 gas are colourless when visible light scatters it? why can't i see N2 and H2 coloured

The simple answer is that the electronic states of nitrogen and hydrogen are very far apart in energy. Both of these gases absorb in the vacuum ultraviolet region of the spectrum. The isolated gas molecules do not exhibit rotational or vibrational spectra, either.

There are emission bands between excited states of N2 and H2 that are in the visible region. You can see many of these if you pass an electric discharge through the gases at low pressure.
 
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1. Why is N2 and H2 invisible to the human eye?

N2 (nitrogen) and H2 (hydrogen) are invisible to the human eye because they are both colorless and do not absorb or emit any visible light. This means that they do not have any specific color that can be detected by our eyes.

2. Can other animals see N2 and H2 in color?

It is possible that some animals, such as certain birds or insects, may be able to see N2 and H2 in a different way than humans. However, since these molecules do not have any color to reflect, it is unlikely that they can be seen in color by any species.

3. Why can we see other gases, like oxygen and chlorine, in color but not N2 and H2?

Gases like oxygen and chlorine have distinct colors because they have different electronic structures and are able to absorb and emit specific wavelengths of light. N2 and H2, on the other hand, do not have these properties and therefore cannot be seen in color.

4. Is it possible to artificially color N2 and H2?

Technically, it is possible to add color to N2 and H2 by using dyes or pigments. However, this would change the chemical composition of the molecules and make them behave differently. Therefore, it is not practical or scientifically accurate to artificially color N2 and H2.

5. How do we know that N2 and H2 are actually colorless?

Scientists have conducted experiments using various methods, such as spectroscopy, to determine the properties of N2 and H2. These experiments have shown that these molecules do not have any color properties and are indeed colorless.

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