PH is the water and it color blue
Answer : There are mainly three isotopes of magnesium found in nature; namely Mg-24, Mg-25 and Mg-26. Out of which Mg-24 has 12 neutrons, Mg-25 has 13 neutrons and Mg-26 has 14 neutrons in their atoms. The number of protons and their atomic masses remains the same for the atom. The relative abundance in nature differs for all the three isotopes. Mg-24 has abundance nearly 80% in nature, Mg-25 has abundance as 10% and Mg-26 has 11.01% abundance.
Answer:
The frequency of the photon is 7.41*10¹⁶ Hz
Explanation:
Planck states that light is made up of photons, whose energy is directly proportional to the frequency of radiation, according to a constant of proportionality, h, which is called Planck's constant. This is expressed by:
E = h*v
where E is the energy, h the Planck constant (whose value is 6.63*10⁻³⁴ J.s) and v the frequency (Hz or s⁻¹).
So the frequency will be:

Being E= 4.91*10⁻¹⁷ J and replacing:

You can get:
v= 7.41*10¹⁶
= 7.41*10¹⁶ Hz
<u><em>The frequency of the photon is 7.41*10¹⁶ Hz</em></u>
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