Answer: Transition from X to Y will have greater energy difference.
Explanation: For studying the energy difference, we require Planck's equation.

where, h = Planck's Constant
c = Speed of light
E = Energy
= Wavelength of particle
From the equation, it is visible that the energy and wavelength follow inverse relation which means that with low wavelength value, energy will be the highest and vice-versa.
As electron A falls from X-energy level to Y-energy level, it releases blue light which has low wavelength value (around 470 nm) which means that it has high energy.
Similarly, Electron B releases red light when it falls from Y-energy level to Z-energy level, which has high wavelength value (around 700 nm), giving it a low energy value.
Energy Difference between X-energy level and Y-energy level will be more.
You can determine this by counting the number of electrons on the last orbital. If the number of electrons on the last orbital (valence electrons) is 8 then it satisfies the octet rule because the compound has mirrored the look of a noble gass or “neutral” charge.
With the info given i would have to say their is no kinetic energy, it's all potential energy.
Answer:
pH= 0.92
Explanation:
HNO3-> H^+ +NO3^-
HNO3 is a strong acid, so it fully dissociates
[HNO3] = 0.12M [H^+] = 0.12M
pH= -log[H^+]
pH=-log[.12] = 0.92
pH = 0.92