Name: Ji Min Kim

Partners: Megan, Kelsey

Date of experiment: September 29th 2010

Factors that affecting the cooling rate of water

Aim: The amount of water that we need, to let the water cool down in the fastest way

Hypothesis: 1) If the amount of water decreases then the time for cooling the water will be faster.2) If the amount of water increases then it will take long time to cool down.

Variables:

Input variable: Amount of water (change as 100ml, 150ml, 200ml)

Output variable: Time for water to cool down

Control variables:

Control variable 1: I will keep it constant by same room temperature

Control variable 2: I will keep it constant by the same fire flame.

Control variable 3: I will keep it constant by measuring the start temperature.

Control variable 4: I will keep it constant by having same beaker. Such as the area, volume…

Control variable 5: I will keep it constant by using same thermometer.

Control variable 6: I will keep it constant by length of the time we measure the temperature (10 minutes)

Materials:

- 250ml beaker (3)- Bunsen Burner- Stopwatch - Retort stand (1)- Measuring Cylinder - Heatproof mat- Lighter

- Long arm clamps- Thermometer- Boss head- Tripod

Method:

1. Set up equipment as shown in Diagram2. Turn the flame on3. Put 100g water on the ‘gauze mat’4. Heat until the temperature reaches to 60 Celsius5. After it went to 60 Celsius, time 10 minutes and record degrees for 1 minute.6. Do same thing as 100ml, 150ml, 200ml…

Results:

Table

Time 100ml 150ml 200ml1 58 59 58.52 57 57 57.53 55 56 56.54 54 55 55.55 53 54 54.56 52 53 547 51 52 538 50 51 529 48 50 51.5

10 47 49 51

Gragph

Conclusion:

There is a pattern in our experiment. As I said in hypothesis if the water increases then it will take long time to cool the water down. I guess it is hard to see with that graph, technically I didn’t know how to make less distance of temperature. So do as Ms. Jenna. +I want to comment on my group. Our group did the experiment last, because I guess I was the one that working for the drafting the experiment. Well Megan did some parts too. However, Megan and Kelsey were talking to each other and I guess they were talking about not related to science. Plus when it was the time for preparing the equipment and set up for the experiment, I guess I did all things. Like setting up, Megan was just stand next to me and Kelsey, she even didn’t know how to sep up the equipment. So I hope that next time, Ms. Jenna will choose the groups.

Evaluation:

Our group did the exact same steps as what I wrote in the “Method” and it gives me this data. However, our group need to improve, because we didn’t measure the first 0 degree. Also in that time when we were doing the experiment, actually our group didn’t know how to start it. First I asked Ms. Jenna to open the Bunsen burner. Opening the Bunsen burner was quiet hard. I always keep thinking about I will get hurt. However, I opened the Bunsen burner. I got surprised at first, but it was okay. Back to the topic, I guess our group needs to improve by following the instruction carefully. (We got wrong several times). Also I hope that I can make a graph really well on the computer.

This experiment gave me how to open the Bunsen burner, however I will remember this experiment as part of a bad memory. It was hard for me to do almost all things. I am happy that this experiment end quickly.