Specific Heat of Lead Lab PDF

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Chem 1405/4H11 04 February 2021 Specific Heat of Lead Purpose: To determine the specific heat of lead. Safety: 1. Wear Safety goggles 2. Closed toe shoes 3. Gloves 4. Apron 5. Tongs Procedure: Record all data in Data Table 1. Record the mass of Pb on the balance. 2. Place lead in oven which is set to 200℃. 3. Fill calorimeter with 100 mL of water and turn stirrer on. 4. Record mass of water with density at 25℃ being 0.998 g/mL using the formula d m ¿ and m ¿ dv . v 5. Record initial temperature of water. 6. Record volume of water. 7. Record initial temperature of Pb. 8. Allow water to stir for about 20-30 seconds to allow a baseline temperature. 9. Remove Pb from oven with tongs and place Pb in calorimeter, replace calorimeter lid and record highest temperature.

Data Table

Pb Mass of Metal (g)

31.1761

Volume of Water (mL)

100

Mass of Water (g)

99.8

Initial Temperature of Water ℃

25

Initial Temperature of Metal ℃

200

Max Temperature of Water + Metal ℃

26.45

Questions: 1. Calculate the changes in temperature of the water. 2. Calculate the heat, in J, gained by the water using the following equation: q(water)T(water)C(water)=, given Cwater= 4.184 J/(Kg) 3. Calculate the changes in temperature of the Pb. 4. Remembering that the heat gained by the water is equal to the heat lost by the metal, calculate the specific heat of lead in J/K×g. 5. Calculate the percent error in the specific heat value that you determined experimentally. The accepted value for Pb is 0.130 J/K×g. Calculations: Trail 1 Lead: ∆T(lead) = 200℃ - 26.45℃ = 173.55℃ Trail 1 water: ∆T(water) = 26.45℃ - 25℃ = 1.45℃ Heat gained by water = (99.8)(26.45-25)(4.184) = 605.46664J 605.46664 Specific Heat of Lead 0.112J/K•g ¿ (31.1761)(173.55) ¿ ¿ 0.112−0.130∨ 0 .130 ×100 = 13.8% % Error = ¿

Conclusion: The main objective of this experiment was to measure the heat of lead after placed into water and allowed to reach equilibrium. The method to measure was a thermometer and calorimeter. The specific heat of the lead was 0.112J/K•g and the accepted value was 0.130J/K•g, which is 13.6% error. I followed the instructions exactly, but I feel I could have had more precise measurements if I was given a more specific amount of time to allow the lead to sit in the oven rather than assume the lead had reached 200℃ . There were also small issues with the program itself which could account for more human error in my methods....