How to determine whether a liquid is pure water or not besides boiling the liquid?

Explanation:

Aside the boiling point of water, another colligative property that can be used to identify pure water (or not) is the freezing point. Water freezes at 0 °C, but with the presence of impurities, there is a freezing point depression of the water. Thus, if the water is not pure, the liquid could freeze at a temperature lower than 0 °C (with a negative sign like -8 °C).

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

the formula for the conversion of temperature from degree celsius to kelvin is:

the sample of water at is converted to kelvin temperature by using the above formula as:

on comparing the two samples of water at or we can say that at and at respectively. the difference between the temperatures of two samples of water is:

hence, one can say that the sample of water at is greater than the sample of water at by .