CHEM 200 CC Chemistry Atomic Emission Spectra Project

1. Watch this video

•Data in a table that you create:volume cold water, room temp, density at that temp, mass of cal+ cold water, mass of cal + cold water + hot water  •Calculated data with proper sig figs in a table (with calculations with units): Change in temperature for hot water, for cold water, heat capacity of the calorimeter  • Data in a table for delta H rxn: volume HCl, Density of HCl, specific heat of HCl, C_ cal average from at , mass of Zn(s), initial and final temperatures of HCl.  •Calculated data with the same stipulations as above: change in temperature HCl, heat of the solution (HCl), moles of zinc, heat of reaction, enthalpy of reaction, average enthalpy of reaction for all trials, standard deviation of average enthalpy of all trials. Remember to include to use the heat capacity of your calorimeter for your zinc calculations (not the heat, the heat capacity, because the heat changes), percent error.  •Discussion questions. Version A
Calorimetry Part II + Extra
Fall 2020
Student A wanted to find the heat capacity of the styrofoam cups they were using for the
experiment. Student A did two trials and times the experiment every 30 seconds due to time
constraints in the lab.
Table 1. Heat Capacity Data
Trial One:
Trial Two:
Mass of Calorimeter and Cold
Water (g):
71.348
68.302
Mass of Calorimeter with Cold
and Hot Water (g):
118.423
116.723
Volume of Cold Water (mL):
49.9
49.8
Temperature of Hot Water (℃)
75.5
70.0
Specific Heat Capacity of
Water ((J/g･℃):
4.184
4.184
0.99799
0.99799
Density of Cold Water at 21.0
℃ (g/mL):
Table 2. Temperature versus Time to Find Heat Capacity
Time (s)
Trial One Temperature (℃):
Trial Two Temperature (℃):
0
21.5
22.0
30
21.2
21.5
60
21.2
21.0
90
21.2
21.0
120
21.2
21.0
150
21.2
21.0
180
63.2
72.3
210
60.5
64.2
240
49.1
58.0
270
45.1
47.0
300
45.0
47.0
330
45.0
47.0
360
45.0
47.0
Version A
Calorimetry Part II + Extra
Fall 2020
*Highlighted temperatures are the last measured temperature before the hot water was added.
Student A then did four trials to find the Enthalpy of Zinc. Again due to time constraints in the
lab the experiment was done in 30 second intervals.
Table 3. Enthalpy of Reaction Data
Trial One:
Trial Two:
Trial Three:
Trial Four:
Mass of Zinc (g):
0.514
0.505
0.502
0.528
Volume of 6M HCl
(mL):
49.8
49.9
49.9
49.8
Density of HCl (g/mL):
1.098
Specific Heat Capacity
of HCl (J/g･℃):
4.10
Table 4: Temperature versus Time to find Enthalpy of Zinc
Time (s)
Trial One
Temperature (℃):
Trial Two
Temperature (℃):
Trial Three
Temperature (℃):
Trial Four
Temperature (℃):
0
20.5
20.5
23.0
21.0
30
20.0
20.0
23.0
21.9
60
20.0
20.0
22.0
21.5
90
20.0
20.0
22.0
21.5
120
20.0
20.0
22.0
21.5
150
24.1
21.5
25.0
23.6
180
25.5
23.0
25.0
23.6
210
26.0
24.5
27.0
24.9
240
26.1
24.5
27.0
24.9
270
25.5
25.8
27.0
26.3
300
25.0
25.0
27.0
26.3
330
25.0
25.0
27.0
26.3
360
25.0
25.0
27.0
26.3
*Highlighted temperatures are the last measured temperature before the metal was added.
Version A
Calorimetry Part II + Extra
Fall 2020
Assignment:
For the extra experiment you will create you a data table, the calculated results table, and the
graphs for finding the temperature of the water. If you need help on how to do a double
trendline on excel I have posted a video in the Google Drive. Using the information from excel,
to find your ∆T of the water, you will need to find the heat capacity of the styrofoam cups. You
will also calculate the average and standard deviation of the heat capacity.
For the Enthalpy of Zinc experiment you will create you a data table, the calculated results
table, and the graphs for finding the temperature of the water. If you need help on how to do a
double trendline on excel I have posted a video in the Google Drive. Using the information from
excel, to find your ∆T of the water, you will need to find the enthalpy of zinc. You will also
calculate the average and standard deviation of the enthalpy of zinc. Don’t forget you must
add in the heat capacity of the styrofoam cups when calculating the enthalpy of zinc.
Don’t forget to show your sample calculations. You will then answer the Discussion/Questions
in the Lab Manual.