A student observed that when powdered sugar at –1 °C was added to ice at –1 °C all of the ice
melted.
Which of the following statements explain this observation?
1 Sugar has given the water molecules energy.
2 The melting point of the mixture is higher.
3 The melting point of the mixture is lower.
A 1 only
B 1 and 3 only
C 3 only
D 2 only
E 1 and 2 only
Hi!
is the answer C?
a solute lowers the melting point and raises the boiling point of water so 3) is correct
i don’t think C6H12O6 and H2O would react? So it wouldn’t give the water molecles energy?
You are right, the answer is C. The sugar only dissolves in water which is a physical process, not a chemical reaction, so energy is not involved here:)
Thank you for your answer! Do you mind explaining it more broadly? I don’t exactly understand how can you determine that the glucose doesn’t provide the ice energy
Hi!
Juliette and Darius are absolutely correct with their reasoning. This is how i thought about it.
the reason why 1. is incorrect because Sugar does not provide any energy to the water as both the sugar and ice are at the same temperature and for heat to transfer there must be a temperature gradient b/w them as we know heat moves from high temperature to low temperature reigon.
Hope this helps:)
yes it sure does, thank you!