When water at 50 C is added to ice at -12 C, heat is transferred from hot water to ice.
- Heat given out by water = Heat absorbed by ice
Calculating the heat released by hot water:
ΔT

Calculating heat absorbed by 16 g of ice: Ice at
is converted to ice at
and then ice at
to water at 
ΔT + 
+ 
q = 405.12 J +5336.8 J =5741.92 J
- Heat given out by water = Heat absorbed by ice
-(
m = 27.4 g
Therefore, 27.4 g water at
must be added to 16 g of ice at
to convert to liquid water at 
I suggest you to go with C !! it is absolutely wrong sentence !!
increasing the gas particles will increase the collision between them so !!
your answer is C !!
Increase, because you need heat to melt a solid to a liquid, so the temperature will have to get greater.
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