Answer:The functional groups in an organic compound can frequently be deduced from its infrared absorption spectrum. A compound, C5H10O2, exhibits strong, broad absorption across the 2500-3200 cm^1 region and an intense absorption at 1715 cm'^-1. Relative absorption intensity: (s)=strong, (m)-medium, (w) weak. What functional class(cs) docs the compound belong to List only classes for which evidence is given here. Attach no significance to evidence not cited explicitly. Do not over-interpret exact absorption band positions. None of your inferences should depend on small differences like 10 to 20 cm^1. The functional class(es) of thla compound is(are) alkane (List only if no other functional class applies.) alkene terminal alkyne internal alkyne arene alcohol ether amine aldehyde or ketone carboxylic acid ester nitr
<u>Answer:</u> The longest wavelength of light is 656.5 nm
<u>Explanation:</u>
For the longest wavelength, the transition should be from n to n+1, where: n = lower energy level
To calculate the wavelength of light, we use Rydberg's Equation:

Where,
= Wavelength of radiation
= Rydberg's Constant = 
= Higher energy level = 
= Lower energy level = 2 (Balmer series)
Putting the values in above equation, we get:

Converting this into nanometers, we use the conversion factor:

So, 
Hence, the longest wavelength of light is 656.5 nm