Aim: To determine the specific heat capacity of brass using calorimetry, the understanding of the relationship between heat and temperature and the concept of heat transfer, using the equation; Q=mc∆T. Also to evaluate the data collected by comparing the experimental value to the accepted value using analytical skills.
Method:
• We heated up a brass weight by immersing it into boiling water for a while in order to assure that the metal’s temperature was the same as of the water.
• We then placed the brass weight into the calorimeter and took a series of readings of the temperature of the water inside in order to find the maximum temperature reached.
• We found the value of heat added to the cold water and the inner cup of the calorimeter by using our measurements and inserting it into the equation Q=mc∆T.
• We found the value of heat taken from the brass weight also, using the same equation.
• The specific heat capacity of the brass weight was then calculating by manipulating the fact that the heat taken from the brass weight is equal to the negative value of the heat added to the cold water.
We followed the method given in the lab manual for the most part, with the following considerations in order to reduce systematic errors.
• We ensured that the same scale was used for every weight measurement made for the purpose of this experiment. This was to avoid systematic errors due to the possibility of slight discrepancies in the accuracy of the different scales.
• We ensured that the person reading the thermometer avoided parallax and therefore systematic error by ensuring that their eyes were parallel to the level of liquid inside.
• We ensured that there was minimal volume of water transferred from the vessel containing the bo...
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...o move the ice freezer to the table where our setup is in order to minimize the contact of the ice with the atmosphere and the carrying vessel in order to minimize the amount of ice melted. This would decrease systematic error by consequently decreasing the calculated value of Lf.
Conclusion:
By using calorimetry, our understanding of the transfer of heat and the relationship between heat and temperature, we determined that the latent heat of melting of the ice was 3.4105Jkg-1 ± 0.6105 kg-1.
This value agrees with the accepted value, and we were able to identify the possible major causes in the slight discrepancies as random error and possibly systematic error due to the traveling distance between the freezer and the set up by comparing the percentage deviation and the final percentage of uncertainty, and also by critically evaluating our method of the experiment.
Experimental Summary: First, my partner and I put the marshmallow and cheese puff on T-pins and used the Electronic Balance to measure the mass of each of them. Next, we put 100 mL of water in the 100 mL Graduated Cylinder and poured it into the 12 oz. soda can. We measured the temperature of the water with the thermometer. After
Two equations were used in this experiment to determine the initial temperature of the hot water. The first equation
Start with the hot water and first measure the temperature. Record it. 8. Then pour 40 ml into the beaker. You can measure how much water was used by looking at the meniscus.
Tf-Ti). Next, subtract the initial temperature, 25 degrees from the final temperature, 29 degrees putting the change in temperature at 4 °C. To calculate the heat absorbed by the water in calorimeter, use the formula (q = mCΔT). Plug in 50 mL for (m), 4.184 J for (C) and 4 °C for the initial temperature (ΔT), then multiply.
put in the pot. If the person knew if changing the volume of a substance will not change the boiling point, but only alter how much time it takes for the substance to reach the temperature. Then the person would know that it would be better to not put too much water in the pot, because it would take longer for the water to boil.
In this experiment, there were several objectives. First, this lab was designed to determine the difference, if any, between the densities of Coke and Diet Coke. It was designed to evaluate the accuracy and precision of several lab equipment measurements. This lab was also designed to be an introduction to the LabQuest Data and the Logger Pro data analysis database. Random, systematic, and gross errors are errors made during experiments that can have significant effects to the results. Random errors do not really have a specific cause, but still causes a few of the measurements to either be a little high or a little low. Systematic errors occur when there are limitations or mistakes on lab equipment or lab procedures. These kinds of errors cause measurements to be either be always high or always low. The last kind of error is gross errors. Gross errors occur when machines or equipment fail completely. However, gross errors usually occur due to a personal mistake. For this experiment, the number of significant figures is very important and depends on the equipment being used. When using the volumetric pipette and burette, the measurements are rounded to the hundredth place while in a graduated cylinder, it is rounded to the tenth place.
4. Pour hot water into one beaker and adjust the temperature to 39°C by adding colder water if needed
Possible sources of error in this experiment include the inaccuracy of measurements, as correct measurements are vital for the experiment.
Discussion: The percent of errors is 59.62%. Several errors could have happened during the experiment. Weak techniques may occur.
Introduction: A phase change is a result from the kinetic energy (heat) either decreasing or increasing to change the state of matter (i.e. water, liquid, or gas.) Thus saying, freezing is the phase change from a liquid to a solid which results from less kinetic energy/heat. Also, melting is the phase change from a solid to a liquid which results from adding kinetic energy/heat. So, the freezing and melting point of something is the temperature at which these phase changes occur. Therefore, a phase change will occur when a vial of 10 mL of water is placed into a cup of crushed ice mixed with four spoonfuls with 5 mL of sodium chloride for 30 minutes. If 10 mL of water is placed in an ice bath, it will then freeze at 5 degrees Celsius because the kinetic energy will leave quicker with the ice involved. The purpose of this lab is to observe what temperature the water must be to undergo a phase change.
By adding fresh cold water it should cool the copper calorimeter. By making sure I do these checks before I do the experiment means that I should be able to get accurate results as the test will have been run fairly and hopefully successfully as there should not have been anything gone wrong. To make sure all the measurements are correct, I will also run checks. These checks when recording the data are. Make sure to check the thermometer to see what temperature the water is at the start, so I am able to see what it has to be when its been heated by 10 degrees.
Specific heat capacity of aqueous solution (taken as water = 4.18 J.g-1.K-1). T = Temperature change (oK). We can thus determine the enthalpy changes of reaction 1 and reaction 2 using the mean (14) of the data obtained. Reaction 1: H = 50 x 4.18 x -2.12.
The objective of this experiment was to identify a metal based on its specific heat using calorimetry. The unknown metals specific heat was measured in two different settings, room temperature water and cold water. Using two different temperatures of water would prove that the specific heat remained constant. The heated metal was placed into the two different water temperatures during two separate trials, and then the measurements were recorded. Through the measurements taken and plugged into the equation, two specific heats were found. Taking the two specific heats and averaging them, it was then that
- Each teaspoon may not have been equal. Measurements were made based on judgment and not exact measurements.
The variable in regards to using a Bunsen burner and thermometer bath enables a higher control over the temperature of the water as the temperature can be monitored and increased/decreased easily.