Spectrophotometry

Question 1

What is spectrophotometry?

Answer 1

The measurement of light absorption or transmission

Question 2

Is spectrophotometer quantitative a qualitative?

Answer 2

Quantification

Question 3

How is absorption measured?

Answer 3

Enzyme catalysed reactions measured by substrate disappearance/ product appearance

Question 4

What is C?

Answer 4

Speed of light (cm. Sec-1)

Question 5

What is the sign for wavelength (cm)?

Answer 5

upside down V

Question 6

What is the sign for frequency (sec-1)?

Answer 6

V

Question 7

What is a nanometer(nm)

Answer 7

10-9m

Question 8

What is a angstrom (A)

Answer 8

10-10m

Question 9

Wave number =

Answer 9

1/wavelength

Question 10

What is the region of X-rays?

Answer 10

0.1 - 100nm

Question 11

What is the wavelength region of uv?

Answer 11

100 -400nm

Question 12

What is the wavelength region of visible?

Answer 12

400-800nm

Question 13

What is the wavelength region of Ir?

Answer 13

800nm -1um

Question 14

What is the effect of X-rays and uv on molecules?

Answer 14

Subvalence electrons excited to higher levels

Question 15

What is visible rays effect on molecules?

Answer 15

Valence electrons excited to higher energy levels

Question 16

What is Ir effect on molecules?

Answer 16

Molecular vibration

Question 17

What is the wavelength of red light?

Answer 17

650hm or 6500A or 6.5x10-5cm

Question 18

What are the parts of a spectrophotometer?

Answer 18

Entrance slit, exit slit, sample holder, detector

Question 19

What does the entrance slit do?

Answer 19

Focuses an intense beam of light

Question 20

What’s the purpose of the exit slit?

Answer 20

Allows you to detect the wavelength at which the sample will be read

Question 21

The sample holder usually has a path length of?

Answer 21

1cm

Question 22

What is the purpose of the detector?

Answer 22

Usually hooked up to a display unit