Which of the following are true based on this comparison? [closed]








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In the following chart, the horizontal line is **time** and vertical line is **temperature**. $K$ and $L$ are solid matters that are placed in two identical pots within the same room and are being heated up with identical heaters.


[![enter image description here](https://i.stack.imgur.com/1XKEi.png)](https://i.stack.imgur.com/1XKEi.png)


(Translation: Sıcaklık = temperature, Zaman = time, dak (dakika) = minute, maddesi = substance)


Which ones of the following are true?


A-) If $K$ and $L$ are different matters, they have the same mass.


B-) If masses of $K$ and $L$ are different, they can be the same matter.


C-) If masses of $K$ and $L$ are equal, they are different matters.


I chose "only $B$" which turned out to be wrong while the correct answer is "$B$ and $C$" and in the explanation it said "You picked the wrong answer because you think different matters can't have the same boiling/melting point." which is true because they **can't**, right? 




A is not true - no such connection exists.
B is true (and given the same temperature indicating the phase transition it is in fact likely that K and L are the same matter).
C is true and can be explained as follows: if K and L have the same mass, they must have different [specific heat capacities](https://en.wikipedia.org/wiki/Heat_capacity), defined as:


$$
c = \frac{\text{the amount of energy to be added to raise the temperature by 1°C}}{\text{mass}}
$$


This is a property that is unique for each matter - same as the melting and boiling point. It can be said to be a function of the matter. Note that the $T(t)$ graphs appear to start at the same temperature, but it takes longer to heat L than K to 85°C although the same heating is applied.


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