Answer:
The correct answer is option false.
Explanation:
Molality of the solution defined as moles of substance present in 1 kilogram of solvent.
Moles = 

Mass of percent (w/w%) of the solution is defined as amount of solute present in 100 grams of solution.

So, if want to inter-convert molality into mass percent we can do that without knowing density of solution.
Mass of solution = Mass of solute + Mass of solvent
I think is 5 because you use density is found by mass divide by volume.
Answer:
5.82 ×10⁴ j
Explanation:
Given data:
Mass of water = 25.7 g
Amount of heat to evaporate it = ?
Molar heat of vaporization = 4.07×10⁴ j/mol
Solution:
First of all we will calculate the number of moles of water.
Number of moles = mass/ molar mass
Number of moles = 25.7 g/ 18 g/mol
Number of moles = 1.43 mol
Energy needed for one mole is 4.07×10⁴ j.
For 1.43 mol:
1.43 mol × 4.07×10⁴ j/ 1mol
5.82 ×10⁴ j
Answer:
In a mixture, each substance is still the same and don't really combine. In a compound, the substances are chemically combined (so the substances that went in have technically changed).
Explanation: