CHM2046L Final Exam UF Spring 2026-2027
Beer's Law calibration curve: equation: y=22066x + 0.008
Use the following data to generate a calibration curve yes, all points fall on the trendline or are very close. R2 = 0.9998
of Absorbance vs Concentration at λmax = 420.6 nm.
y = absorbance
concentration 1: 6e-5 M; absorbance 1: 1.330
concentration 2: 2e-5 M; absorbance 1: 0.451 x = solute concentration (mol/L)
concentration 1: 1e-5 M; absorbance 1: 0.239
concentration 1: 2e-6 M; absorbance 1: 0.042
a y-intercept of 0 indicates 0 absorbance at 0 M concentration of colored
solute
Record the equation and analyze your data:
- do all of the data points fall on the trendline? Is your
R2 value greater than 0.990?
- what does y represent?
- what does x represent?
- why should the y-intercept of the linear trendline be
very close to 0?
Serial Dilution: x = 6.67 ml
- Perform calculations to determine the amount of x = 10 ml
6.00x10-5 M stock solution needed to prepare 20.00 mL
of 2.00x10-5 M dye solution. x = 4 ml
- Perform calculations to determine the amount of
2.00x10-5 M stock solution needed to prepare 20.00 mL
of 1.00x10-5 M dye solution.
- Perform calculations to determine the amount of
1.00x10-5 M stock solution needed to prepare 20.00 mL
of 2.00x10-6 M dye solution.
, CHM2046L Final Exam UF Spring 2026-2027
using this Beer's Law calibration curve equation, for absorbance 1:
y=22066x + 0.008, at λmax = 420.6 nm, determine the x = 1e-4 M
concentrations for each of the absorbances values
below: for absorbance 2:
x = 7.02e-5 M
absorbance 1: 2.224
absorbance 2: 1.558
No. These concentrations obtained from the absorbances, y = 2.224 and
if absorbance 1 is from a 1e-3 M stock solution and
y = 1.558, do not follow Beer's Law. The concentrations calculated do not
absorbance 2 is from a 1e-4 M stock solution, do all of
match the stock solution concentrations, 1e-3 M and 1e-4 M. The
these data points follow Beer's Law? (did the
maximum absorbance value that follows Beer's Law is 1.330 at λmax =
concentrations you obtained using the equation match
420.6 nm because 1.330 falls on the trendline. The absorbances, y =
the concentrations of the stock solutions?). If not, why?
2.224 and y = 1.558, do not follow the trendline because their
(***hint: look at the excel graph you generated and
absorbances surpass the maximum absorbance at λmax = 420.6 nm.
determine the maximum absorbance at λmax = 420.6
nm that falls on/very close to the trendline)
consider that you have a 100 mM stock solution and you 3.0 ml stock
need to prepare 10 ml of a 30 mM solution.
7.0 ml DI water
How many ml of the stock solution do you need?
How many ml of deionized water do you need?
enter each of your answers to 2 sig figs
visible light wavelengths red: 630-750 nm
orange: 590-630
yellow: 560-590
green: 480-560
blue: 430-480
violet: 400-430
if a solution appears green, approximately what f. 700 nm
wavelength of light is it absorbing?
if the solution is green, then it is absorbing red light (opposite color on
a. 400 nm the color wheel)
b. 470 nm
c. 520 nm
d. 580 nm
e. 630 nm
f. 700 nm
(image of wavelengths provided when u flip this card)
, CHM2046L Final Exam UF Spring 2026-2027
for a red dye, a calibration curve for absorbance versys 25.3
concentration was plotted and it yielded a trendline
with an equation of y= 31,870x + 0.0012. If an unknown
sample of red dye has an absorbance of 0.807, what is
the concentration of the sample?
enter your answer in units of micromolar (μM)
the concentration of dye in Solution A is 23.8 M. A serial 5.85
dilution is performed to make Solutions B and C.
In the 1st dilution, 7 ml of Solution A is diluted with 12 ml
of water to make Solution B.
then, 2 ml of Solution B is then diluted with 1 ml of water
to make Solution C.
What is the concentration od dye in Solution C?
3 sig figs in molarity
suppose you make a calibration curve as described in c. absorbance
the pre-lab information and get a linear equation in the
form of y=mx+b. Assuming the path length is 1 cm, what
is represented by the "y" in the equation?
a. concentration
b. molar absorptivity
c. absorbance
d. path length
How does concentration affect rate of reaction? Increasing reactant concentration increases reaction rate.
factors that increase the rate of reaction: - increasing temperature
- increasing reactant concentrations
Beer's Law calibration curve: equation: y=22066x + 0.008
Use the following data to generate a calibration curve yes, all points fall on the trendline or are very close. R2 = 0.9998
of Absorbance vs Concentration at λmax = 420.6 nm.
y = absorbance
concentration 1: 6e-5 M; absorbance 1: 1.330
concentration 2: 2e-5 M; absorbance 1: 0.451 x = solute concentration (mol/L)
concentration 1: 1e-5 M; absorbance 1: 0.239
concentration 1: 2e-6 M; absorbance 1: 0.042
a y-intercept of 0 indicates 0 absorbance at 0 M concentration of colored
solute
Record the equation and analyze your data:
- do all of the data points fall on the trendline? Is your
R2 value greater than 0.990?
- what does y represent?
- what does x represent?
- why should the y-intercept of the linear trendline be
very close to 0?
Serial Dilution: x = 6.67 ml
- Perform calculations to determine the amount of x = 10 ml
6.00x10-5 M stock solution needed to prepare 20.00 mL
of 2.00x10-5 M dye solution. x = 4 ml
- Perform calculations to determine the amount of
2.00x10-5 M stock solution needed to prepare 20.00 mL
of 1.00x10-5 M dye solution.
- Perform calculations to determine the amount of
1.00x10-5 M stock solution needed to prepare 20.00 mL
of 2.00x10-6 M dye solution.
, CHM2046L Final Exam UF Spring 2026-2027
using this Beer's Law calibration curve equation, for absorbance 1:
y=22066x + 0.008, at λmax = 420.6 nm, determine the x = 1e-4 M
concentrations for each of the absorbances values
below: for absorbance 2:
x = 7.02e-5 M
absorbance 1: 2.224
absorbance 2: 1.558
No. These concentrations obtained from the absorbances, y = 2.224 and
if absorbance 1 is from a 1e-3 M stock solution and
y = 1.558, do not follow Beer's Law. The concentrations calculated do not
absorbance 2 is from a 1e-4 M stock solution, do all of
match the stock solution concentrations, 1e-3 M and 1e-4 M. The
these data points follow Beer's Law? (did the
maximum absorbance value that follows Beer's Law is 1.330 at λmax =
concentrations you obtained using the equation match
420.6 nm because 1.330 falls on the trendline. The absorbances, y =
the concentrations of the stock solutions?). If not, why?
2.224 and y = 1.558, do not follow the trendline because their
(***hint: look at the excel graph you generated and
absorbances surpass the maximum absorbance at λmax = 420.6 nm.
determine the maximum absorbance at λmax = 420.6
nm that falls on/very close to the trendline)
consider that you have a 100 mM stock solution and you 3.0 ml stock
need to prepare 10 ml of a 30 mM solution.
7.0 ml DI water
How many ml of the stock solution do you need?
How many ml of deionized water do you need?
enter each of your answers to 2 sig figs
visible light wavelengths red: 630-750 nm
orange: 590-630
yellow: 560-590
green: 480-560
blue: 430-480
violet: 400-430
if a solution appears green, approximately what f. 700 nm
wavelength of light is it absorbing?
if the solution is green, then it is absorbing red light (opposite color on
a. 400 nm the color wheel)
b. 470 nm
c. 520 nm
d. 580 nm
e. 630 nm
f. 700 nm
(image of wavelengths provided when u flip this card)
, CHM2046L Final Exam UF Spring 2026-2027
for a red dye, a calibration curve for absorbance versys 25.3
concentration was plotted and it yielded a trendline
with an equation of y= 31,870x + 0.0012. If an unknown
sample of red dye has an absorbance of 0.807, what is
the concentration of the sample?
enter your answer in units of micromolar (μM)
the concentration of dye in Solution A is 23.8 M. A serial 5.85
dilution is performed to make Solutions B and C.
In the 1st dilution, 7 ml of Solution A is diluted with 12 ml
of water to make Solution B.
then, 2 ml of Solution B is then diluted with 1 ml of water
to make Solution C.
What is the concentration od dye in Solution C?
3 sig figs in molarity
suppose you make a calibration curve as described in c. absorbance
the pre-lab information and get a linear equation in the
form of y=mx+b. Assuming the path length is 1 cm, what
is represented by the "y" in the equation?
a. concentration
b. molar absorptivity
c. absorbance
d. path length
How does concentration affect rate of reaction? Increasing reactant concentration increases reaction rate.
factors that increase the rate of reaction: - increasing temperature
- increasing reactant concentrations
