This is an incomplete question, the image for the given question is attached below.
Answer : The wavelength of photon would be absorbed, 
Explanation :
From the given diagram of energy we conclude that,
Energy at ground state, A = 400 zJ
Energy of 2nd excited state, C = 1050 zJ
Now we have to calculate the energy of the photon.
Now we have to calculate the wavelength of the photon.
Formula used :
As, 
So, 
where,
E = energy of photon = 
= frequency of photon
h = Planck's constant = 
= wavelength of photon = ?
c = speed of light = 
Now put all the given values in the above formula, we get:
Therefore, the wavelength of photon would be absorbed,
Answer:
Explanation:
21. Atoms are not created or destroyed means that atoms that you begin with are the atoms that you will end with. The catch is that the atoms will rearrange to give you new compounds, but the atoms that you initially had are the atoms you will still have after reaction. For eg, if you started with eggs and made omelet. Omelet is a "new" compound, but the atoms that were in the eggs have rearranged to become the omelet so can you see that atoms were not created or destroyed to make the omelet.
22. Yes because amount of products you make depends on how much reactants you have. For eg, I need two graham cracker(GC), one marshmallow(M), and one chocolate (C) to make a s'more. If I get more of each item then I can make more s'mores and consequently having minimum amounts results in less s'mores that I make.
23. Not possible, due to law of conservation of matter and energy. Atoms cannot be created nor be destroyed, they are simply rearranged. For eg, Taking A + B cannot give you a new compound with a chemical formula D or XZ. A + B can however give you AB which is rearrangement of the starting atoms.
24. Chemical equation is balanced when atoms on reactant side and atoms of product side are in equal counts. I have attached a graphic below for more help.
Explanation:
Magnesium has atomic number 12. It will be distributed in K, L, M shell in the following way:
K shell can accommodate a maximum of 2 electrons.
L shell can accommodate a maximum of 8 electrons and
M shell will accommodate 2 electrons
So the configuration becomes 2, 8,3
The substance that can be classified as being soluble in water would be salt. The solution is D. Salt specifically is composed of ions and the ionic compound dissociates within water.
