Sunscreens are designed to protect the skin from harmful rays from the sun in th
ID: 1022271 • Letter: S
Question
Sunscreens are designed to protect the skin from harmful rays from the sun in the region of 280-400nm. A sunscreen product labeled SPF 15 transmits 7.0% of light at 280 nm. What is the absorbance of sunscreen at 312 nm.A.) 2.00 B.) 1.15 C.) 0.185 D.) None Sunscreens are designed to protect the skin from harmful rays from the sun in the region of 280-400nm. A sunscreen product labeled SPF 15 transmits 7.0% of light at 280 nm. What is the absorbance of sunscreen at 312 nm.
A.) 2.00 B.) 1.15 C.) 0.185 D.) None
A.) 2.00 B.) 1.15 C.) 0.185 D.) None
Explanation / Answer
Assuming the transmittance is same at 280 nm and 312 nm
Absorbance = 2- log %T
Absorbance = 2 - log 7
Absorbance = 2 - 0.845
Absorbance = 1.15
SO the correct answer is option (B)