Select the correct statement(s) :a)All electromagnetic radiation travel with speed of light in vaccum.b)Energy of photon of UV light is lower than that of yellow light.c)He+and H have similar spectrum.d)The total energy of an electron in unielectronic specie is greater than zero.Correct answer is option 'A C'. Can you explain this answer?

Question

Answer

Both He+and H , contains 1electron .so, their spectrum will be similar.....

Answer

What happens if they are isoelectronic.remember that energy of photon emitted (or the frequency) would be equal to the difference of energy levels of the orbits and the energy of orbits is proportional to z^2/n^2.Obviously z(atomic number) is not same for h and he+ hence frequency of radiation or the spectrum should not be same

Answer

Explanation:

Statement a: All electromagnetic radiation travel with speed of light in vaccum.
This statement is true. According to the theory of relativity, the speed of light in a vacuum is a constant value of approximately 3 x 10^8 meters per second. Electromagnetic radiation, which includes visible light, radio waves, microwaves, X-rays, and gamma rays, all travel at this speed in a vacuum.

Statement c: He and H have similar spectrum.
This statement is also true. The spectrum of an element refers to the specific wavelengths of light that it emits or absorbs. Both helium (He) and hydrogen (H) have similar spectra because they both have one electron in their outermost shell. The energy levels and transitions of this electron result in similar emission and absorption spectra for both elements.

Statement b: Energy of photon of UV light is lower than that of yellow light.
This statement is false. The energy of a photon is directly proportional to its frequency, as described by the equation E = hf, where E is energy, h is Planck's constant, and f is frequency. Ultraviolet (UV) light has a higher frequency than yellow light, which means it has higher energy photons. Therefore, the energy of a photon of UV light is higher than that of yellow light.

Statement d: The total energy of an electron in unielectronic specie is greater than zero.
This statement is also false. In an unielectronic species, such as hydrogen (H) or helium (He), there is only one electron present. The total energy of this electron can be calculated using the energy formula E = -13.6/n^2 electron volts, where n is the principal quantum number. The negative sign indicates that the electron's energy is lower than zero, which means it is bound to the nucleus. The energy becomes more negative (i.e., lower) as the electron's distance from the nucleus increases.

In summary, the correct statements are:
a) All electromagnetic radiation travel with speed of light in vaccum.
c) He and H have similar spectrum.

Answer

Yaa option C is correct but option A is also correct as well so it should be a multiple Anwer question.....

Answer

Because this are isoelectric species

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