Effect of Water Volume on Ice Melting Times

The experiment proves two types of heat transfer. Those two are Convection and Conduction but the experiment will be mostly focusing on Convection. Convection is one of the three heat transfer methods. Convection is a heat transfer method where the fluid such as liquid travels away from its heat source, it carries the heat energy with it. In this experiment, the source of the heat was the bunsen burner and the conductor of the heat from the bunsen burner was a metal ball (Oldenburg, 2019). When the metal ball was heated up and placed into a beaker of water, which contained a single ice cube,, the source of the heat within the experimental setup became the metal ball. As the metal ball is extremely hot, the temperature of the water rapidly increased. As the water heated up, the ice cube also started to melt. This proved that there has been a heat transfer from the metal ball to the ice. Convection works by circulation. For example, in the water, when the water is heated up, the hot water rises and the cold water descends resulting in heating the water as the hot water moves away from the heat source and cold water gets closer to the heat source.

Convection can be used in various different places with a different method. An example of a specific problem that has been addressed through the use of convection techniques is in the operation of a nuclear power plant. The transfer of thermal energy produced from the nuclear fuel rods to the surrounding water is an example of convection. In a nuclear power plant, the thermal energy produced by nuclear fission is transferred to the water surrounding the nuclear fuel rods. Steam is formed due to a large amount of thermal energy produced by nuclear fission in the nuclear fuel rods, which is used to drive turbines and generate electrical energy. One of the problems we use convection is the Nuclear Power Plant. The nuclear power plant runs by splitting the atoms from uranium. This generates massive heat and steam which runs the generator to produce heat. The temperature of the uranium inside the rod which is located underwater inside a rod to prevent a nuclear meltdown. These rods are 270-degree Celsius hot but sometimes rises to 1200 degree Celsius which is high enough to melt the rod causing a nuclear meltdown. This is where a cooling system using convection comes in.

Nuclear power plants are very fragile telling us that it requires a huge amount of cooling. Nuclear power plants always use convection as its heat transfer method as it is the most effective way to release the heat. The pump pumps the coolant and then meets the fuel rods which is around 200-degree celsius when it makes contact with the coolant. The pump will continuously pump the water into the uranium rods which will cool the rod and increase the temperature of the coolant. This proves that there has been a heat transfer using Convection. This helps problems to solve the efficiency of the powerplant compared to other sources of energy which uses a different type of heat transfer method.

(Appindix 1)

 Heat transfer is an effective way to convert thermal energy to electricity. To give an example of methods of producing electricity using heat, Solar panels use radiation as its heat transfer method from the sun and the nuclear power plant uses convection as its heat transfer method. Radiation does not require particles to transfer energy. On the other hand, convection does require particles to transfer energy. Solar panels are eco-friendly, as they use the heat energy from the sun that gets transferred using radiation to produce electricity. The nuclear power plant uses uranium as its power source. The nuclear atom from uranium which causes a lot of heat. The water is filled inside the tank that contains the rod contained with uranium. When water makes contact with the uranium rods, it produces steam which goes through the turbines and produces electricity. When steam is created, the water that made contact with the uranium rod and heated up shows that there has been a heat transfer using convection. (Afework et al., 2019)

Efficiency is important when producing electricity comes in. The less energy is wasted, the more efficient it becomes. The nuclear power plant’s efficiency is around 33%~37%. But the efficiency of a newer generation of nuclear powerplant is known as 45%. The solar panel’s efficiency depends on which material is used. A monocrystalline solar panel’s efficiency is around 27%, and polycrystalline and thin-film is around 22% effective. The efficiency also differs depending on the weather of the region that the solar panels are installed at and the performance of the inverter also changes the efficiency. This evidence tells us that using convection in real life is more efficient which means, it is economically more friendly in some parts. However, using radiation as its heat transfer method in real life is much more environment-friendly as it does not require any contact with the source.

Aim

Will the volume of water affect the time it takes to melt the ice?

Hypothesis

The ice will melt faster when the volume of the water is greater. This is because of how the ice gets melted by the water. Water melts the ice because the temperature of the surrounding is higher than the freezing point of the water which is 0 Celsius. The ice will eventually cool the water down as time passes. If the volume of the water is greater, it takes a longer time for the ice to cool the water down. (Hoff, 2017)

Equipment

-          metal ball

-          Tap water (Enough water to run three trials for 5 different volumes of water)

-          Bunsen Burner

-          A 1000 ml beaker

-          Heatproof mat

-          Ice cubes (From the same container)

-          Stopwatch

-          Matches

-          Ball & Ring Apparatus

Method

1)     Prepare all the materials

2)     Place the fireproof mat on a flat surface

3)     Place the bunsen burner on top of the fireproof mat

4)     Check if the gas valve is in an off position

5)     Connect the bunsen burner with the gas

6)     When ready to light the bunsen burner, turn the gas valve on

7)     Use the striking surface on the matchbox to light the matches on fire

8)     Hold the end tip of the match and hold it right on top of the bunsen burner

9)     When the bunsen burner is on fire, place the match on the heatproof surface to completely turn the fire off

10) Filling the beaker before applying heat to the metal ball will create a fair result as it is difficult to fill the beaker with water during and after heating the metal ball as it will eventually lose heat if it is not located on top of the bunsen burner.

11) Place the ice cube tray next to the beaker is easier to apply ice to the water. In this situation, having a partner for the experiment will run the experiment quicker and heat up the metal ball exactly for 3 minutes.

12) Fill the beaker with the correct amount of volume of water (300ml, 400ml, 500ml, 600ml, 700ml)

13) Apply heat to the metal ball by holding it on top of the bunsen burner using a ball & ring apparatus

14) Use a stopwatch to check if 3 minutes passed. But do not stop the stopwatch yet.

15) After 2 minutes and 55 seconds of heating, apply a cube of ice into the beaker

16) When 3 minute passes, drop the metal ball into the beaker filled with a correct volume of water and one ice cube.

17) Do not move or touch anything and do not stop the stopwatch

18) When the ice fully melted, take out 3 minutes from the displayed time

a)     If the stopwatch displays 7:43, it took 4:43 to melt the ice as it took three minutes to heat the metal ball.

19) To make the result more accurate, repeat from step 4 multiple time.

Safety

-          The metal rod attached to the metal ball also conducts heat. While heating the metal ball up, do not touch the metal rod as it is also very hot

-          Do not lean over the bunsen burner

-          Do not put any object that could catch on fire near the bunsen burner

-          Double check if the gas valve is at an off position after using the bunsen burner

-          Make sure that the matches are fully out of the fire

Result

(Time in Minute:Second)

Graph

Discussion

The experiment proved convection by hearing up a metal ball and dropping it into a beaker filled with ice and different volume of water. The expected result was that the ice cube will melt faster if the volume of the water is greater. The freezing point of the water is 0-degree Celsius. The temperature of the tap water should have been the room temperature. The ice melted due to the temperature of the water being higher than the ice. To be more detailed, the ice particles gather the heat energy from the air and the water. The gathered energy is powerful enough to break apart the ice particles. This makes the ice particles to break into small pieces allowing it to move much more freely like liquid particles (Childow, n.d.). This causes the ice to eventually melt. The larger volume of water will have greater energy making the ice to melt quicker. The experiment has proved that the hypothesis was correct. If the result for 300ml and 700ml gets compared, it took 300ml an average time of 4:34 and 700ml took an average of 3:24. As the metal ball was heated hotter than the freezing point of the water which creates ice, it heated up the water causing the ice to melt. Even though the metal ball was heated the same time, the ice particles had enough energy to cool the water down if the water had lesser volume. However, the beaker with more volume caused the ice particles to break apart quickly as the water had more energy to melt the ice due to its volume (Childow, n.d.). The metal heated up due to its vibration of atoms. When the atoms start to vibrate, they intend to move away from each other. This is called a thermal expansion. After the metal ball was heated up and made contact with the water, the heat transfer occurred causing a convection current. A convection current is when the hot liquid rises and cold liquid drops creating a current (Appendix 2). This current causes the water temperature to rise.

The experiment had a few difficulties that were difficult to solve. The ball & ring apparatus that was used made the experiment to be inaccurate the most. The metal ball that was connected to the apparatus had an unbalanced centre of gravity. The metal ball was connected to a metal chain which then was connected to a metal pole then the handle. The metal ball was heavier than the handle causing it to tilt towards where the metal ball was located at the front of the apparatus. No other tool was used to hold the entire apparatus making the apparatus to rely on human hand which isn’t always stable. The entire apparatus moved up and down and when it had a bit of movement, it would swing sideways causing the metal ball to move away from the bunsen burner a bit. This could slightly change the temperature of the metal ball. The second issue that the method had was the ice. As explained, ice melts in room temperature which was higher than the freezing point. After a few trials, the ice started to melt by itself. This could tell that the ice cube that was used last will have a smaller volume of ice cube than the ones that were used in the first few trials.

These errors caused the result to be inaccurate. To improve this, the experiment should have been proceeded in this directions. The ice cubes had to be taken out of the fridge only when it is needed. After taking one ice cube out, the tray has to be returned to the fridge immediately. As the experiment was preceded in different days, the bunsen burner was replaced every lesson. As the bunsen burner was replaced every test period, the collar on the bunsen burner was also wasn’t in the same position making the bunsen burner to have different amount of air intake which determines the temperature of the flame (Appendix 3).

Appendix

(1)  (The Boiling Water Reactor (BWR), 2019)

(2)

(3)

Sources

• Hoff, A. (2017). Why Does Water Melt Ice?. [online] Sciencing. Available at: https://sciencing.com/water-melt-ice-5135067.html [Accessed 15 May 2019].
• Afework, B., Hanania, J., Stenhouse, K. and Donev, J. (2019). Nuclear power plant – Energy Education. [online] Energyeducation.ca. Available at: https://energyeducation.ca/encyclopedia/Nuclear_power_plant [Accessed 16 May 2019].
• The Boiling Water Reactor (BWR). (2019). [image] Available at: https://www.nrc.gov/reading-rm/basic-ref/students/animated-bwr.html [Accessed 16 May 2019].
• Childow, I. (n.d.). How does an Ice Cube Melt. [online] J2e.com. Available at: https://www.j2e.com/st+nicholas+ce+middle+school/csf15/PHS/How+does+an+Ice+Cube+Melt(1)/ [Accessed 16 May 2019].
• Physicsclassroom.com. (2019). Rates of Heat Transfer. [online] Available at: https://www.physicsclassroom.com/class/thermalP/Lesson-1/Rates-of-Heat-Transfer [Accessed 17 May 2019].
• Oldenburg, a. (2019). greenTEG | 3 Types of Heat Transfer | Conduction, convection, and radiation: three types of heat transfer. [online] Greenteg.com. Available at: https://www.greenteg.com/heat-flux-sensor/about-heat-flux/3-types-of-heat-transfer/ [Accessed 17 May 2019].