Woodward-UV Flashcards
mamatay na tali ko ani ba
The wavelength of UV light absorbed by a compound.
lambda max
What happens to the energy difference between the ground and excited state with conjugated dienes?
Decreases
What absorbs light in the UV region of the electromagnetic spectrum?
Conjugated dienes and polyenes
When the energy difference between the ground and excited state decreases, the number of conjugated π bonds _______.
increases
UV radiation from the sun is high enough in energy to cleave bonds, forming ___________ that can ________________ & ______________.
radicals,
prematurely age skin,
causes skin cancer
Wavelength range for UV-A
320 nm to 400 nm
Wavelength range for UV-B?
290 nm to 320 nm
Wavelength range for UV-C?
<290 nm (less than 290 nm)
_________ and ________ are filtered out by the sun.
UV-A and UV-B
A highly conjugated colored pigment in the skin that serves as the body’s natural protection against the harmful effects of UV radiation.
Melanin
A _______________ can offer added protection because it contains conjugated compounds that absorb UV light.
commercial suncreen
Prolonged exposure to the sun can ____________________________.
allow more UV radiation to reach your skin than melanin can absorb.
___________ does not burn your skin but can still cause long term damage to the skin cells.
UV-A
It is used to calculate the wavelength of maximum absorption of conjugated dienes and polyenes.
Woodward-Feiser rules
A type of diene generally involves the attachement of 2 trans dienes.
Transoid diene/ Heteroannular diene
