Question

Part E. Determination of a Calorimeter Constant A student doing a calorimetry experiment similar to this one is asked to find the calorimeter constant for the calorimeter he is using. Cold water is added to the calorimeter, the temperature is measured. Water is heated on a hot plate. The temperature is measured. Some hot water is added to the calorimeter with the cold water. The final temperature is measured taken along the way. The data is given below. . The masses are Trial 3 25.6738g 50.2011g 19.9°C 90.2°C 75.0680g Mass of empty calorimeter: Mass calorimeter with cold water Trial I 25.4356g 50.1927g Trial 2 25.4361g 20.1°C 85.6oC 74.3392g Temperature of cold water in calorimeter 19.7C 83.5°C Temperature of hot water Final temperature of water mixture Use the data given above to calculate the calorimeter constant including the average and standard water mixture 48.9°C 49.5°C 52.2°C deviation. Be sure to give correct units and significant figures. As always, work must be shown to receive credit.

Calculate Part E all the information is given

Answer 1

For the first trial

calculate the heat gained by the cold water

Q cold = mass * specific heat * (Temperature difference)

Q cold = 50.1927 * 4.184 * (48.9 -19.7) =6132.18 Joules

calculate the heat lost by the hot water

mass of hot water = mass of total water - mass of cold water

mass of hot water = 75.22 - 50.197 = 25.0273 C

Q hot = 25.0273 * 4.184 * (48.9 - 83.5) = -3623.112 Joules

Now apply

Q calorimeter + Q hot + Q cool = 0

Q calorimeter = 3623.112 - 6132.18 = -2509.068 Joules

Q calorimeter = heat capacity * temperature difference

Temperature differece = (48.9 - 19.7) = 29.2 C

Q calorimeter = -2509.068 = heat capacity * 29.2

heat capacity = 2509.068 / 29.2 = 85.92 Joule / gram

Here is an image with the other calculations

75.22 74.3392 75.068 50.1927 50.1938 50.2011 25.0273 24.1454 24.8669 temp cold w final temp 19.7 48.9 20.1 49.5 19.9 52.2 temp hot w 83.5 85.6 90.2 -34.6 -36.1 38 Q hot Q cool 3623.11212 3646.97916 6258.3236 3953.63816 6826.34558 6132.1827 Q cal 2509.07058 2611.34444 2872.70741 heat capacity -85.9270745 88.8212394 88.93831