UV - VISIBLE SPECTROSCOPY

Question 1

What is the wavelength range for UV spectrum of light?
a) 400 nm – 700 nm
b) 700 nm to 1 mm
c) 0.01 nm to 10 nm
d) 10 nm to 400 nm

Answer 1

d) 10 nm to 400 nm

Question 2

Which of the following comparison is correct for solvent shift on the n –>π* transition of acetone?
a) H20 = CH30H = C2H50H = CHC13 = C6H14
b) H20 > CH30H > C2H50H > CHC13 > C6H14
c) H20 < CH30H < C2H50H < CHC13 < C6H14
d) H20 > CH30H < C2H50H < CHC13 < C6H14

Answer 2

c) H20 < CH30H < C2H50H < CHC13 < C6H14

Question 3

What is the correct order of λmax for n –> σ* transition?
a) R-OH > R-NH2 > R-SH
b) R-OH < R-NH2 < R-SH
c) R-OH > R-SH > R-NH2
d) R-OH < R-SH < R-NH2

Answer 3

b) R-OH < R-NH2 < R-SH

Question 4

What is the correct order of λmax for n –> π* transition for the R-CN, R-NO2, and R-N=N-R?
a) R-CN < R-NO2 < R-N=N-R
b) R-CN = R-NO2 = R-N=N-R
c) R-CN > R-NO2 > R-N=N-R
d) R-CN > R-NO2 < R-N=N-R

Answer 4

a) R-CN < R-NO2 < R-N=N-R

Question 5

What is the correct order of λmax for n–> π* transition for the following three compounds?
a) RCOOH > RCOOR’ > RCONH2
b) RCOOH = RCOOR’ = RCONH2
c) RCOOH = RCOOR’ < RCONH2
d) RCOOH = RCOOR’ > RCONH2

Answer 5

b) RCOOH = RCOOR’ = RCONH2