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Physics help needed :)

The liquid coolant has a freezing point below –20 °C. Explain one other property that the liquid coolant should have
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Sinnoh
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Could you give some more context to the question?
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sgdag
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Original post by Sinnoh
Could you give some more context to the question?

The bowl is used for making ice cream. The walls of the bowl contain a liquid coolant.The bowl is cooled to –20 °C before the mixture is put in the bowl. The bowl causes the mixture to cool down and freeze.
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Sinnoh
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Original post by sgdag
The bowl is used for making ice cream. The walls of the bowl contain a liquid coolant.The bowl is cooled to –20 °C before the mixture is put in the bowl. The bowl causes the mixture to cool down and freeze.

Coolants work by evaporating to remove heat, so it needs to be quite volatile to evaporate at low temperatures.
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sgdag
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Original post by Sinnoh
Coolants work by evaporating to remove heat, so it needs to be quite volatile to evaporate at low temperatures

Thank you! Sorry for bothering you but may you help me with this question as well?
Explain why the different thermal conductivities of metal and plastic are important in the design of the bowl.
Reply 5
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Sinnoh
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Original post by sgdag
Thank you! Sorry for bothering you but may you help me with this question as well?
Explain why the different thermal conductivities of metal and plastic are important in the design of the bowl.

I'm guessing there's a diagram - could you post a photo of it?
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sgdag
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Original post by Sinnoh
I'm guessing there's a diagram - could you post a photo of it?

Oops, im on my laptop so im not sure how i get the diagram on here but it is a bowl with an inner metal surface, with a liquid coolant around it and a plastic outer layer. Lol hope that helps xD
Original post by sgdag
Oops, im on my laptop so im not sure how i get the diagram on here but it is a bowl with an inner metal surface, with a liquid coolant around it and a plastic outer layer. Lol hope that helps xD


Plastic is low so the cold doesn’t escape to the surroundings metal is high so the cold reaches the ice cream to freeze it
A high specific heat capacity, so it can absorb a large amount of energy with only a small temperature change.

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