Step two-Pour 50ml (accurately measured) into each container.
Take the temperature of the water in each container make sure all temperatures are the same. Place lid on each container.
Step three- Take the temperature of the water in each container every minute (time using stop clock) and record results.
A-Copper
B- Glass
C- Hard Plastic
D-Polystyrene
Results Table
Temperature degrees C
Conclusion
The copper can (A) took 11 minutes to cool from 84 c to 60 c.
The glass beaker (B) took 13 minutes to cool from 84 c to 60 c.
The hard plastic cup took about 12 minutes to cool from 84 c to 60c.
The Polystyrene cup didn’t reach 60 c in our experiment in 14 minutes it reached 62 c.
The results show us that water cooled fastest in the copper can. This is because metal is a conductor of heat. - Copper is a metal thus making it a conductor of heat. The results also show that the water-cooled slowest in the polystyrene cup. This is because it contains pockets of air making it a bad conductor of heat.
Evaluation
I think my investigation was successful; it produced clear results in keeping with my prediction and scientific theory. There were no surprising results.
Although it was hard to get the starting temperature the same it was eventually achieved. Making my results clearer and easier to draw conclusions from.
The investigation was successful but I still feel it could have been improved to make my results more accurate. The measuring of the water was done quickly using a glass beaker to prevent the water cooling before I started my experiment the experiment would have been more accurate if I had measured the water using a measuring cylinder.
Other factors that could be investigated are:
- Surface area.
- Insulation.
- Stirring.
- The use of a lid.
Aim of Investigation
The aim of this investigation is to find out how the Surface area of the opening of the container affects the way hot water cools down to room temperature. I am going to use two glass beakers one with the capacity to hold 200mls of water, with a diameter of 7.5 cm and a surface area of 44.179 cm. The other has the capacity to hold 75mls, with a diameter of 5.5 cm and a surfaces area of 23.75cm.
Prediction and scientific theory
I predict the beaker with the largest diameter, capacity and surface area will retain the least heat and be the fastest to cool down. I have based my prediction on the fact that that more hot air will be able to escape from the beaker with the larger surface area than from the beaker with the smaller surfaces area.
Fair Test
To make the experiment a fair test I will-
- Use the same amount of water.
- Make sure the starting temperature is the same.
- If one is stirred they all have to be stirred.
- If one is blowed the other one must be blowed.
- They must both be the made of the same material.
Step-By-Step
Step one –Boil water
Step two-Pour 50mls (accurately measured) into each beaker.
Take the temperature of the water in each container make sure both temperatures are the same.
Step Three- Take the temperature of the water in each beaker every minute (time using stop-clock) and record results.
A-Diameter 7.5 cm
B-Diameter 5.5 cm
Results Table
Temperature C
Conclusion
The beaker with larger capacity, diameter and surface area (A) took about 5minutes to cool from 79 C to 60 C.
The beaker with the smaller capacity, diameter and surface area (B) took about 8 minutes to cool from 79 C to 60 C.
These results show us that the water-cooled fastest in the beaker with the larger capacity, diameter and surface area. This is because a lot more hot air was able to escape. The beaker with the smaller capacity, diameter and surface area retained the more heat because less hot air was able to escape.
Evaluation
I think this investigation was quite successful although not as successful as the first experiment. The results this experiment produced were less clear because the starting temperatures were very different. It was still possible draw conclusions from the results and these results were in keeping with my prediction and scientific theory.
This investigation was successful but as I did with the first experiment I think improvements could have been made to make my results clearer and more accurate. As in the first experiment the measuring of the water was done quickly using a glass beaker to prevent the water-cooling before I started my experiment. The experiment would have been more accurate if I had measured the water using a measuring cylinder.
I was unable to get the starting temperatures of the water the same. If I had been successful the results would be clearer and easier to draw conclusions from.
