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LAB REPORTPHYMECHANICS II AND THERMAL PHYSICSEXPERIMENT 1METHOD OF MIXTURES: SPECIFIC HEAT CAPACITYBIL NAME GROUP ID NUMBER1) NURFARAH IZZANI EKRAM AS1202L 2020475552DATE OF EXPERIMENT : 12 APRIL 2021DATE OF SUBMISSION : 21 MAY 2021LECTURER’S NAME : DR. HARTINI AHMAD RAFAIETHEORYSpecific heat capaci...

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LAB REPORT

PHY210 MECHANICS II AND THERMAL PHYSICS EXPERIMENT 1 METHOD OF MIXTURES: SPECIFIC HEAT CAPACITY

BIL

NAME

GROUP

ID NUMBER

1)

NURFARAH IZZANI EKRAM AS1202L 2020475552

DATE OF EXPERIMENT : 12 APRIL 2021 DATE OF SUBMISSION : 21 MAY 2021 LECTURER’S NAME : DR. HARTINI AHMAD RAFAIE

THEORY Specific heat capacity of a substance is the amount of heat that must be supplied to increase its temperature by 1˚C for a mass of 1 kg of the substance. Specific heat capacity, c, can be calculated by knowing the amount of heat supplied, Q to a mass, m, of a substance and the resulting increase in temperature, Δθ. When two materials with different temperature are in contact, heat will flow from higher temperature to the lower temperature, until these two materials reach an equilibrium temperature. The rule of calorimetry principle is also known as 𝐻𝑒𝑎𝑡 𝐿𝑜𝑠𝑠=𝐻𝑒𝑎𝑡 𝑔𝑎𝑖𝑛𝑒𝑑. The quantity of heat absorbed or released by a body is given by 𝑄=𝑚𝑐 𝑚𝑐 𝑚𝑐Δ𝜃 𝜃 (1.1) In this experiment, a metal of mass, mm that has been heated to a high temperature, θi is dropped into a mass of water, mw at low temperature, θf. When equilibrium is achieved, the new temperature of the water-metalcalorimeter combination is measured as θm. To arrive at this equilibrium temperature, the water and calorimeter must have gained the heat lost by the metals. By neglecting the heat lost to the surrounding, this situation is expressed by equation: 𝑚𝑚 𝑐𝑚 (𝜃 𝜃𝑖− 𝜃𝑓) = 𝑚𝑤 𝑐𝑤 (𝜃 𝜃𝑓−𝜃 𝜃𝑖 ) (1.2) Where: 𝑐𝑚 = specific heat capacity of metal 𝑚𝑚 = mass of metal 𝑚𝑤 = mass of water 𝑐𝑤 = specific heat capacity of water 4200 J/kg. ˚C 𝜃𝑖 = high temperature θf = low temperature Theoretical value for metal: 𝑐calorimeter = 𝑐cal = 900 J/kg. ˚C 𝑐aluminium = 𝑐al = 900 J/kg. ˚C 𝑐iron = 𝑐fe = 450 J/kg. ˚C 𝑐𝑤 ater =𝑐𝑤 = specific heat capacity of water 4200 J/kg. ˚C

OBJECTIVE 1) To measure the specific heat capacity of several different substances. 2) To find if the specific heat capacity of several different substances can be measured by using method of mixture.

APPARATUS AND MATERIALS 1) 2) 3) 4) 5) 6) 7) 8) 9)

Aluminium block Iron block Calorimeter set Thermometer set Hot plate 500ml graduated cylinder 350ml beaker 500ml beaker 1m thread

PROCEDURES 1) 300ml water was poured into 500ml beaker by using graduated cylinder. 2) The water was heated up until the water boiled.

3) While waiting for water to boil, the mass of aluminium block was measured and recorded.

4) The aluminium block was tied with 50cm thread.

5) The aluminium block was hung by using universal clamp and the block was heated in the 500ml beaker filled with water until the water boiled.

6) The mass of empty calorimeter with stirrer was measured and recorded.

7) 200ml of water was poured into calorimeter. 8) After two minutes, the initial temperature of calorimeter was measured and recorded.

9) The mass of calorimeter with water was measured and recorded.

10) When the water started to boil, the temperature of aluminium block was measured and recorded.

11) The block was quickly pulled out of the boiling water and immersed it into the calorimeter. 12) The highest temperature of the system was measured and recorded before it starts falling while stirring the water.

13) Steps 1 until 12 were repeated using iron block instead of aluminium block.

PRESENTATION OF DATA PARAMETER Mass of block, kg Mass of empty calorimeter, kg Mass of calorimeter + water, kg Initial temperature of water in calorimeter, °C Temperature of boiling water, °C Final temperature of the system, °C Change in temperature of water and calorimeter, °C Change in temperature of block, °C

METAL Al Fe 0.059 0.06 0.376 0.376 0.570 0.570 25.2 25.2 99.4 99.3 28.7 27.2 3.5 2.0 70.7 72.1

ANALYSIS OF DATA Specific Heat Capacity Aluminium

Iron

Percentage Error |𝑥 − 𝑦| 𝑦

× 100%

Aluminium

Iron

Percentage Different 𝑥1 − 𝑥2 |(𝑥1 + 𝑥2 ) ⁄2 | 𝑥100% Aluminium

Iron

DISCUSSION In this experiment, we found out the specific heat capacity of aluminum and iron using the method of mixtures. This was done by taking a piece of metal to find out its mass using the weighing scales, to measure the mass of the metal used in the experiment. Then, the metal was placed in the beaker filled with water and until boiled and measured.Then assumed the temperature measured was the same as the metal’s temperature to use it as the initial temperature. Then it was transferred to a calorimeter filled with water that was measured before to set it as calorimeter and water initial temperature. After transferring the metal quickly into the calorimeter, the highest temperature before its falls down was recorded. The rise in temperature in the calorimeter was also recorded. It is because, when the heat released by the metal and the heat gained by water were the same, it reached the equilibrium. After the experiment was conducted, the result of the specific heat capacity calculated for the metals was not the same as the theoretical value of the specific heat capacity for both metals. This might happen due to a few reasons that had been affected the result of the experiment conducted. Sources of error that might have contributed to this difference include heat loss during the transfer of the metal into the calorimeter, heat loss by the calorimeter itself, and lack of precision of the balance and thermometer used in this experiment. This could be minimized by transferring it as quickly as possible into the calorimeter. Inaccuracies could also arise from human error in reading measurements like mass and temperature. This error can be minimized by using the same person to take and record the reading for mass and temperature. When temperature changes are being measured, one can reduce the error by taking both temperatures with the same thermometer.

Questions a. Calculate the specific heat capacity of Al and Fe metal block. Specific heat capacity calculated of Al is 967.68 J/ Kg °C meanwhile Fe is 533.15 J/ Kg °C.

b. Calculate the percentage difference between your calculated specific heat capacity and its theoretical value. Calculated percentage different between measured specific heat capacity of Al and Fe is 7.25 and 16.92%.

c. Why should you stir the water at the end of the experiment before the temperature reading is taken? Stirring gives you a more accurate measurement. If you don't stir, the heat transfer is limited by natural convection, that is, a film of cool liquid forms around the end of the thermometer and gives an artificially low reading. Stirring disrupts the film and provides much better "forced convection" heat transfer.

d. Why is water used in the experiment as a cooling system? Water has a high specific heat, which means it is difficult to increase the temperature of water. However, water also has the capacity to retain heat, which allows the other substance inside the calorimeter to absorb that heat.

CONCLUSION 1) The specific heat capacity of aluminium and iron measured were 967.68 J/ Kg °C and 533.15 J/ Kg °C. 2) The specific heat capacity of the substances can be measured using the method of mixture.

REFERENCES

1) John, R. (2021). Accuracy and precision in the measurement of temperature. Uwimona.edu.jm. http://wwwchem.uwimona.edu.jm/lab_manuals/c10expt6.html

2) LAB #10 PH-101 - Lab report. (2018). StuDocu; StuDocu. https://www.studocu.com/my/document/queensboroughcommunity-college/principles-of-physics/coursework/lab-10ph-101-lab-report/2150046/view 3) Measuring the Specific Heat Capacity by Method of Mixtures Free Essay Example. (2020, June 2). StudyMoose. https://studymoose.com/measuring-specific-heat-capacitymethod-mixtures-new-essay...