CHMLL 130 RSC Calorimetry & Specific Heat Capacity of Aluminum Exercise

I’m working on a chemistry question and need guidance to help me learn.

C. Calculations (Show all calculations with units on each number and the final answer rounded to the correct significant figures for full credit.)

1. Calculate the mass of the water by using the water’s density (assume it is 1.00 g/mL) and the volume of the water. Remember, density = mass/volume. (4 pts)

Aluminum (Trial 1) –

Aluminum (Trial 2) –

1. Calculate the change in temperature for the water caused by the addition of the metal by subtracting the initial temperature of the water from the final temperature of the water. ?T = T_f – T_i (4 pts)

Aluminum (Trial 1) –

Aluminum (Trial 2) –

1. Calculate the change in the metal’s temperature by subtracting the initial temperature of the metal from the final temperature of the metal. ?T = T_f – T_i (4 pts)

Aluminum (Trial 1) –

Aluminum (Trial 2) –

1. Use the equation: q = m(SH)?T to solve for the amount of energy gained by the water from metal. Remember to use the specific heat capacity of water in this calculation. (8 pts)

Aluminum (Trial 1) –

Aluminum (Trial 2) –

1. Use the equation: q = m(SH)?T to solve for the specific heat capacity of the metal. For q, you found how much energy was gained by the water so you know that same amount of energy was lost by the metal. Therefore, -q_metal = q_water. (8 pts)

Aluminum (Trial 1) –

Aluminum (Trial 2) –

1. Determine the percent error using the equation below and the specific heat capacity of the aluminum from the chart provided in the Background Information portion of the lab as the accepted value. The experimental value is your calculated answer for the specific heat capacity of aluminum from Question 5. (4 pts)

Aluminum (Trial 1) –

Aluminum (Trial 2) –

D. Follow-Up Questions

1. The first law of thermodynamics states that energy lost by one object is gained by another. Explain how you used this law to find the specific heat capacity of aluminum. Reference the work you did in Questions 4 and 5. (6 pts)

1. To determine the specific heat of the metal, you assumed that the amount of heat lost by the metal equals the amount of heat gained by the water. Do you think this is a valid assumption? Explain your reasoning and be sure to discuss your percent error for each trial in your response. (6 pts)

1. Were the results of the second trial better than the first trial? Explain why or why not. Your explanation should compare the percent error for each trial and discuss TWO potential sources of error from the procedure (not “human error” or “calculator error”). (6 pts)

1. Why do you think scientists run multiple trials when they are conducting experiments? Discuss TWO potential reasons they would do so. (4 pts)

Part II: Identifying an Unknown Metal

A. Data Table 2

Complete the Data Table. (5 pts)

UNKNOWN METAL
Letter identifying your unknown metal sample (either A, B, C or D)
Pre-weighed unknown metal mass (g)
Initial temperature of cool water in the calorimeter (oC)
Initial temperature of unknown metal (same as the boiling water in the pot) (oC)
Final temperature of water/unknown metal in calorimeter (oC)

B. Insert the following photo with your name and MEID showing in the photo:

Photo B: Insert a photo of your calorimeter showing your unknown metal submerged in water. The photo should be taken from above. (6 pts)

C. Calculations (Show all calculations with units on each number and the final answer rounded to the correct significant figures for full credit.)

1. Calculate the mass of the water by using the water’s density (assume it is 1.00 g/mL) and the volume of the water. Remember, density = mass/volume. (2 pts)

Unknown metal –

1. Calculate the change in temperature for the water caused by the addition of the metal by subtracting the initial temperature of the water from the final temperature of the water. ?T = T_f – T_i (2 pts)

Unknown metal –

1. Calculate the change in the metal’s temperature by subtracting the initial temperature of the metal from the final temperature of the metal. ?T = T_f – T_i (2 pts)

Unknown metal –

1. Use the equation: q = m(SH)?T to solve for the amount of energy gained by the water from metal. Remember to use the specific heat capacity of water in this calculation. (4 pts)

Unknown metal –

1. Use the equation: q = m(SH)?T to solve for the specific heat capacity of the metal. For q, you found how much energy was gained by the water so you know that same amount of energy was lost by the metal. Therefore, -q_metal = q_water. (4 pts)

Unknown metal –

D. Follow-Up Question

1. Identify the unknown metal by comparing the specific heat capacity you calculated in Question 15 to the chart provided in the Background Information portion of the lab. Explain your choice. Be sure to use numerical data related to specific heat capacity to support your claim. (8 pts)