CHEM 318 VSU Analytical Chemistry Questions

HW #1 for Chem 318Due: Feb. 24, 2023
1. The following table shows readings from an instrument. Please calculate the:
1). Sensitivity of the measurement;
2). LOD (Limit of Detection);
3). LOQ (Limit of Quantitation).
Instrument
Concentration of the
response Note
calibration Solution (µM)
5.2 Background
5.3 Background
5.2 Background
5.35 Background
5.2 Background
5.25 Background
5.15 Background
5.28 Background
5.32 Background
5.25 Background
5.18 Background
5.22 Background
5.29 Background
5.33 Background
5.18 Background
5.24 Background
5.31 Background
5.27 Background
5.14 Background
Calibration
9.25 Solution 1
Calibration
13.32 Solution 2
Calibration
17.45 Solution 3
Calibration
21.53 Solution 4
Calibration
25.59 Solution 5
20
40
60
80
100
2. The following table shows readings from a meter at different sample concentrations.
A. Determine the linearity limit of the meter.
B. Determine the dynamic range of the meter.
C. Determine the sensitivity of the meter.
Concentration (mol/L)
Readings (Volts)
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
0.60
0.65
0.70
0.75
0.80
27.0
28.0
30.0
37.5
45.0
52.5
60.0
67.5
75.0
82.5
90.0
97.5
101.0
103.0
104.0
3. Calculate the frequency in Hertz of
(a). an X-ray beam with a wavelength of 3.03 Å.
(b). an emission line for copper at 324.7 nm.
(c). the line at 632.8 nm produced by a He-Ne laser.
(d). the output of a CO2 laser at 10.6 μm.
(e). an infrared absorption peak at 3.85 μm.
(f). a microwave beam at 1.86 cm.
4. A typical simple infrared spectrophotometer covers a wavelength range from 3 to 15 μm. Express its
range (a) in wavenumbers and (b) in hertz.
5. Calculate the wavelength and the energy in joules associated with a signal at 220 MHz.
6. Convert the following values of absorbance to percent transmittance:
(a). 0.0380
(b). 0.916
(c). 0.325
(d). 0.253
(e). 0.185