Miguel Paulo D. Valdez BS Chem-3 EXPERIMENT 14- Heat Effects and Calorimetry Objective/ Introduction: Heat is a form of energy, sometimes called thermal energy, which can pass spontaneously from an object at a high temperature to an object at a lower temperature. If the two objects are in contact, they will, given sufficient time, both reach the same temperature. Heat always travels from hot to cold objects and two objects will reach an equilibrium temperature. Heat flow is commonly measured in a device called a calorimeter, an insulating container that minimizes heat exchange between its contents and the surrounding. Heat flow in a device called a calorimeter. In this experiment, we should find the heat capacity of the …show more content…
A metal sample weighing 45.2 g and at temperature of 100.0 ˚C was placed in a calorimeter containing 38.6 g of water at 25.2 ˚C. At equilibrium the temperature of the water and metal was 33.0 ˚C. a. What was ∆T for the water? __________ ˚C b. What was ∆T for the metal? __________ ˚C c. How much heat flowed into the water (cwater = 4.184 J/g˚C)? __________ J d. Calculate the specific heat of the metal. __________ J/g˚C e. What is the approximate molar mass of the metal? __________ g/mol 2. When 2.00 g of NaOH were dissolved in 49.0 g water in a calorimeter at 24.0 ˚C, the temperature of the solution went up to 34.5 ˚C. a. Is the solution reaction exothermic? __________ Why? b. Calculate q water. __________ J c. Find q for the reaction as it occurred in the calorimeter. __________ J d. Find the ∆H for the solution of 1.00 g NaOH in water. __________ J/g e. Find molar ∆Hsol’n for
Ø Then I will record the temperature of the water in the calorimeter, using a thermometer to give a good degree of accuracy.
11. What is the lowest temperature at which 70 grams of NaNO3 can be dissolved in 100 grams of H2O? 6-8.7
During this experiment/lab we had to undergo a process that would create our own calorimeter and increasing the total energy captured. By using 80ml of water in the breaker having two holes for the thermometer and for the air to escape. The thermometer came through the top and the cup covered of the beaker at the bottom. We had the option to pick a Styrofoam cup or a Soda Can. Our group picked the Styrofoam. So we covered the cup in aluminum inside and out. When combusting the chip we determined that the total energy captured increased.
Figure 1. The Dependency of Water on Temperature. From 12.0 °C - 20.0 °C the equation of best fit line was found to be y=-0.00162(g/((mL* °C)) )x+1.0015(g/mL) and the equation from 20.0 °C – 30.0 °C was found to be y=-0.000256 (g/((mL* °C)))x+1.0034 (g/mL).
In part A of the experiment we added 100 degree Celsius water to room temperature and tracked the temperature of the mixture to see how much it changed. Using this information we were able to calculate how much energy was given off by the how water and how much energy was absorbed by the cold water. The difference of the absolute values of these two values divided by the difference in temperature gave us the calorimeter constant. The calorimeter constant is an important value because it allow us to calculate how much energy is absorbed by the calorimeter in other reactions. Our calorimeter constant makes sense because it is a smaller value and with the colorimeter being Styrofoam, and insulator, the amount of heat absorbed by the calorimeter
The purpose of this laboratory is to determine the experimental quantities of heat transfer and specific heat capacity in a laboratory situation..
The heat of combustion produced increases the temperature of the calorimeter system. About 10 to 15 minutes after ignition the heat exchange between the calorimeter bomb and the water surrounding it in the inner vessel is completed. The temperature rise is then measured and serves to calculate the gross calorific value Ho. This calculation is possible only if under the same test conditions the heat capacity C of the adiabatic system has been determined previously by burning a reference
Record the time and measure the temperature of the solution after 1 minute since the magnesium being placed inside the solution.
The initial temperature of the water was recorded with a thermometer so a change in temperature could be determined. This probe was then placed in the sandwich bag while sealed to observe the temperature inside the assumed calorimeter.
Part 2: Using the “Density of Water (g/mL) vs. Temperature (℃)” on the back of the lab worksheet, the density of water at the recorded temperature was identified. The density was recorded for further use. The mass of water with metal was calculated by subtracting the mass of the jar and the the mass of
After building the calorimeters, the formula (Heat Capacity) = ((Heat lost by hot water) -(Heat gained by cold
The heat gained by the unknown metal and the cool water(2) equals the heat lost by the hot water(1).
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Cold water250 ml of beaker filled with ice (cold water)Its temperature was 59.6 = 60 oC
Supplies necessary for completing the experiment were a gram scale, at least one Styrofoam cup, at least two glass beakers, at least one thermocouple for measuring temperature, an ice bath to cool down the water and a microwave to heat the water. The beakers were used to first measure out the correct amount of water with the gram scale. The weight of the beaker was taken into effect and subtracted from the ending weight of the beaker and water combined. After two beakers were filled with the appropriate amount of water for each experiment according to Table I, the beaker containing the water to be chilled was lowered into an ice bath to reduce the temperature of the water. The beaker containing the water to be heated was put into the microwave and heated until the correct temperature was obtained. After verifying the temperature of the two liquids, they were mixed together into a Styrofoam cup. A thermocouple was quickly inserted and stirred in the water to maintain a uniform temperature reading. Once the temperature stabilized, the final temperature was recorded