Heat of Solidification Lab-Writeup

base In chemistry, warmheartednesss require a certain(prenominal) add together of susceptibility in the attain of average kinetic energy (temperature) to freeze. To relegate the temperature a heart requires to freeze, it must endure a certain nitty-gritty of instigate energy (a form of energy transferred from sensation object to another, because of a temperature difference). When a substance reaches its freezing point and begins to freeze, its temperature remains ageless until it is completely frozen.However, in order to fly the coop a substance must go done a energy change, creating the problem, What energy changes occur when a runny cheeringifies? . To top the problem, a hypothesis was proposed, stating When a substance begins to solidify, it releases oestrusing energy, because a substance must reach its change of circle ( wakening plant take to freeze) by losing a certain amount of kindle, in order to solidify. In order to test this hypothesis, a essay wa s performed. Materials and MethodsIn the experiment, the materials required were 1 bestride exemplification in a test provide with the weight of the test supply labeled, a 250 mL beaker, a ringstand, a conducting wire gauze, a graduated cylinder, a etna Burner, a styrofoam calorimeter, and a thermometer. To perform the experiment, first of totally the calorimeter was filled with 100 mL of pee using a graduated cylinder, and the temperature of the urine was represent and recorded. Next, the beaker was filled 3/4 full with peeing and placed on the stand of the ringstand above a softly burning flame from the Bunsen Burner.Then, the salient number of the test electron tube and rise was found and recorded, and the tube was placed in the beaker. subsequently the climb in the tube melted, the tube was placed in the calorimeter, using a wire gauze. Lastly, once the climb up in the tube solidified, the temperature of the urine supply in the calorimeter was deliberate an d recorded. Results Data Recorded During Experiment survey climb on and test tube41. 2 gravitational constantsTemperature piss after modifying26 ? C Mass give up test tube21. 0 gramsTemperature urine system in the beginning wakeing systeming16 ? C Mass wax20. 2 gramsTemperature change10 ? CVolume water used100 mLMass of water used100 grams In the data postpone above, the mass of the wax was found by subtracting the mass of the empty test tube from the mass of the wax and test tube, bighearted an resoluteness of 20. 2 g. To find the mint of water used, the mass of the water was compute by the density of the water, good-looking an answer of 100 g. To find the temperature change of the water, the temperature of the water after rageing was subtracted by the temperature of the water before heating, giving an answer of 10 ? C. CalculationsAfter the experiment, the heat gained by the water from the wax in the calorimeter was figure using the shape q = mC? T, where C equa led 4. 18 J/g * ? C. After the corresponding determine were plugged in, the equation 100g(4. 18 J/g * ? C. )(26? C-16? C) was created and solved for an answer of 4180 J of heat gained. After the amount of heat gained was found, the heat released per gram of wax (heat of lot) was cypher using the equation 4180 J/20. 2g, giving an answer of 206. 93 J released per gram of wax.Although the heat released per gram of wax, found through the calculations, was 206. 93 J, the accepted value was 150. 0 J/g, because of this, the percent wrongdoing was calculated using the formula(measured actualactual)100. After the set were plugged in, giving the equation(206. 93 J/g 150. 0 J/g150. 0 J/g)100, the percent fault was found to be 38%. countersign After the results were found, a conclusion was worn-out up supporting the hypothesis. In the experiment, the temperature of the water increased from 16 ? C to 26 ? C after the wax solidified.This showed that the wax must bemuse released heat en ergy, in order to cause the temperature of the water to change, callable to temperature requiring heat to change. In a experiment, at that place are many different feasible consultations of scientific error. In the experiment that was preformed, twain possible sources of error were determined. The first source of error found was, the thermometer may rescue miss-measured the temperature of the water after the wax solidified, withal superior or low, which would have caused the heat of solidification to be too high or low.The other source of error was the wax may not have fully solidified, which would have made the heat of solidification too low, cod to the wax not fully releasing its heat energy. To better understand the experiment that was preformed, summery enquirys were asked. The first question asked was, The heat of burn of wax is 45,000 J/g. Explain why there is such a large difference between the heat of solidification and heat of conflagration in scathe of the typ e of change.To answer the question, a solution was made Due to the heat of combustion of wax being the heat released from the chemical reaction between atomic number 8 and wax, it is a chemical change and because the heat of solidification of wax is a forcible change and chemical changes release a significantly larger amount of heat then(prenominal) physical changes, the heat of combustion of wax releases a much larger amount of heat. The second question asked was The amount of heat released by the lot was is equal in magnitude to the amount of heat that the wax indifferent when it melted.Explain why this is so in terms of the positioning of molecules in liquids vs. solids. To respond to this question the response In order to change the establishment of molecules from a solid to a liquid state, the wax must absorb a certain amount of heat and in order to return to a solid state, it must release the energy it absorbed. In the last question, the following was asked Predict th e military force of the change in the mass of the wax used or volume of water in the calorimeter on the following parameters.Assume all variables remain constant other then the one listed. If twice the amount of wax or half the amount of water was used in the experiment, how would the temperature, heat absorbed by the water and the calculated heat of solidification change. Explain your predictions for the heat of solidification. In the answer responding to the question, it was stated, both the temperature and heat absorbed by the water would increase, save the heat of solidification would stay the analogous, due to the wax continuing to release the same amount of heat per gram of wax.