Module 2: Biochemistry Topic 1 Application: Properties of Water Scientific Investigation Report 3. Why don't all liquids display a temperature versus density relationship similar to that of water? All liquids don't display a temperature versus density relationship because different liquids have properties that are different from each other, making them more dense or less dense, instead of having identical properties as water. 4. If a single molecule does not have a temperature, what does temperature measure? If a single molecule does not have a temperature, that means that the temperature is measuring the amount of kinetic energy shown by the molecules. 5. Why is ice less dense than water? Ice is less dense than water because the structure of the molecules in the water changes as the water freezes. This causes it to become more uniform, increasing the space between the molecules, and thus making ice or frozen water to have a lower density than water. This occurs because when water freezes, it freezes from top to bottom, which allows the ice to float on top of water, showing that it has a lower density. 6. What would happen to our apparatus if the water in it froze? If the water was to freeze it would break the apparatus. This is because Water expands as it freezes, meaning that it would probably break/crack our apparatus. Conclusion Compose three to four sentences describing an overall conclusion based on your data. Were your hypotheses true or false, and how do you know? Use the data and notes that you collected from your investigation to form your conclusion. Make sure that you include information that you gained from data analysis to support your conclusion. In conclusion, my hypothesis that as the temperature decreases, the density will increase was correct. The data I collected throughout the lab supports my hypothesis as well. The temperature started at 20
℃
and as it got lower, the density did the complete opposite. As the temperature went down from 20
℃
to 17.28
℃
all the way to 0.57
℃
, the density went up. This can be shown through the column height section. As the column height decreases, the density increases. Therefore, for all the temperatures decreasing, the column height also decreased, showing that density increased. Thus, the data from the table shows that my hypothesis was true. This also shows that the relationship between the density and temperature of the water is a inverse relationship, which is what my hypothesis stated Experimental Sources of Error Provide responses to the following questions: Are there any sources of error? If so, what are they, and what could be done to minimize error? Some sources of error that could occur in this experiment is that I may not read the data correctly, which would lead me to mis-write and and eventually even mis-graph it. I may also just mis-graph the data points even if the data is accurate. Another source of error is that the thermometer, or any other tool that is being used, is broken or not outputting accurate data due to a malfunction. Something that could be done to minimize the error is to take your time so that you can accurately make sure that you are reading and plotting the data correctly. Another thing that can be done to minimize error is to make sure that everything is working properly before starting the experiment. Experimental Sources of Error “No outside sources were used.” 3
