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Lab with only one measurement

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It's my first IB year and I've got a teacher who is new to the IB programme, so I suspect that he does not know all the specifics of the programme. However I might be too hasty in that assumption and would like to ask you is it possible to make a decent IB lab report of the experiment we conducted.

Topic: Measuring the melting heat of ice.

We installed the electronic heat sensors in calorimeter, full of water of certain temperature. Then we took some ice, which temperature we've measured too and put it in the water. We had to record the temperature of the water, as soon as the ice completely melted.

My question is: does anyone know, how to do a lab report, when there's only one measurement?

What should I take as the variables?

How can I process the data?

I would be very thankful for any tips.

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Most experiments need at least 5 measurements and preferably 2 trials per measurement. I would assume your x axis to be time and y axis would be temperature.

I would note any trends on the lines you get from graphing your data. Does the change in temp slow down as the ice melts? Is there a possible asymptotes (somewhere around 0C possibly?) You need to jut ask questions about the data and answer them. You could also do q=mc(delta)T if you want to find how much energy that mass of ice removed from the environment...

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Thanks a lot for the response. I'll surely follow your hints.

Unfortunately we didn't measure time. The change of the temperature gradually slowed down, i guess it went more or less like 1/x, I might be mistaken. Is there any point in making such a graph if I don't have any time data?

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No you kind of can't make any time relation without a time measurement. So what did you measure? O.o

You have the change in temperature vs....the mass of the ice you put in maybe? Mass of the water that was changing temperature?

Edited by Drake Glau

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That's the problem;/ The data I've collected:

  • mass of water
  • mass of ice
  • mass of the calorimeter
  • initial temperature of the water
  • temperature as soon as the ice completely melted in the water
  • initial temperature of ice

I am supposed to use that q=mc(delta)T equation, however the problem is with the data processing and variables. I'd say the problem is that it was rather an indirect measurement, than laboratory. However the teacher said that we have to find our way through data. The problem is that he would be using normal IB mark scheme.

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Use your data to find the amount of heat the ice absorbed. Then you can divide that value by the moles of ice present (mass/molar mass).

When you use q=mc(delta)T your m should be the mass of the water, delta t is the final temp minus the initial temp and your q should be positive and will be the amount of energy taken from the water by the ice in order to melt.

I guess at the end of it you would have a value for how much energy is needed to melt 1 mole of water...

*sidepoint* in your evaluation the ice could easily absorb energy from everywhere around it, not just the water, so your results are going to be WAY off. Just so you know :P

Edited by Drake Glau

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