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Chemistry IA help needed - Freezing point depression of water

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Hello! I am an HL chemistry student who is looking for a relatively easy but interesting chemistry IA topic, and it seems like I found one - freezing point of depression of water. This topic has actually fascinated me for many years, so it will be quite interesting to investigate it. However, I am not sure how to proceed. First of all, I do not know which independent and dependent variables I should choose. Here is an approach I have been thinking of:

  • Independent variable: the concentration of a certain salt (for example, NaCl) dissolved water. I can use 5 different concentrations of NaCl. 
  • Dependent variable: time taken for ice cubes to melt.
  • Method: covering the top of an ice cube with the NaCl solution and measuring the time it takes for the ice cube to melt. 

Does this sound like a good idea, or is it too simple? Also, when melting the ice cubes, where should I keep them? Would it be okay to observe the melting process at room temperature, as in a classroom, or must I emulate cold conditions by for example making an ice bath?

Basically, I would really really appreciate any help, feedback or guidance. I will seriously love you forever!

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Calligative properties describe state changes (eg change in melting of boiling temperature). It's indirect and more difficult to measure kinetics. Better to measure temperature.

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18 minutes ago, kw0573 said:

Calligative properties describe state changes (eg change in melting of boiling temperature). It's indirect and more difficult to measure kinetics. Better to measure temperature.

Hmm, I see. I don't quite understand what you mean with temperature though, would you mind elaborating and perhaps guiding me a bit towards how I should measure it? Thank you for the response by the way!

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When you look at the equation for freezing/melting point depression, you will see that there is no dependence on time, but there is only the change in freezing point. It's more difficult to try to process your data when you look at time to melt because it does not directly (solely) depends on the change in melting point. 

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