Answer : The molecular weight of a substance is 157.3 g/mol
Explanation :
As we are given that 7 % by weight that means 7 grams of solute present in 100 grams of solution.
Mass of solute = 7 g
Mass of solution = 100 g
Mass of solvent = 100 - 7 = 93 g
Formula used :

where,
= change in freezing point
= temperature of pure water = 
= temperature of solution = 
= freezing point constant of water = 
m = molality
Now put all the given values in this formula, we get


Therefore, the molecular weight of a substance is 157.3 g/mol
Answer :- Electrical energy
Explanation :-
Geothermal energy is too large scale
solar energy is inefficient
Nuclear does more harm
Answer: 3378.4mL
Explanation:
density of Gasoline = 0.74g/mL.
Volume of gasoline in milliliter = ?
mass of gasoline = 2.5kg
(Since density is in grams per millilitre, convert mass in kilograms to grams)
If 1kg = 1000grams
2.5kg = 2.5 x 1000 = 2500grams
Recall that density is obtained by dividing the mass of a substance by its volume
i.e Density = Mass / Volume
0.74g/mL = 2500grams/Volume
Volume = (2500 grams / 0.74g/mL)
Volume = 3378.4mL
Thus, the volume of gasoline is 3378.4mL
The liquid that is expected to have the weakest intermolecular interaction is the liquid that has the lowest boiling point and surface tension.
<h3>What is boiling point?</h3>
The term boiling point refers to the temperature at which the atmospheric pressure and the pressure of the liquid becomes equal. The greater the intermolecular forces of attraction between molecules the higher the boiling point of the solid. Also a high surface tension indicates a strong intermolecular forces of attraction between molecules.
The liquid that is expected to have the weakest intermolecular interaction is the liquid that has the lowest boiling point and surface tension.
Learn more about boiling points: brainly.com/question/2153588