In an investigation of the electronic absorption spectrum of a particular element, it is found that a photon having λ = 500 nm provides just enough energy to promote an electron from the second quantum level to the third. from this information, we can deduce select one:
a. the energy of the n = 2 level
b. the energy of the n = 3 level
c. the sum of the energies of n = 2 and n = 3
d. the difference in energies between n = 2 and n = 3
e. all of these

d

Explanation:

The energy of the photon corresponds to the energy gap between the second and third energies levels, the energy required to remove from the second level to the third level. Thus, the energy of the photon corresponds to a difference in energies between two levels, not to the absolute energy of a given level.

what is the general relationship between a galaxy's distance from earth and its speed?

the answer is:

the farther away a galaxy is from us, the faster it is moving away from us.

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

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