Determine the freezing point of a solution that contains 78.8 g of naphthalene (c10h8, molar mass = 128.16 g/mol) dissolved in 722 ml of benzene (d = 0.877 g/ml). pure benzene has a melting point of 5.50°c and a freezing point depression constant of 4.90°c/m.0.74°c4.76°c4.17°c1.68°c1. 33°c

0.74°C

Explanation:

The freezing point depression is a colligative property that can be calculated using the following expression.

ΔTf = Kf . b

where,

ΔTf: depression in the melting point

Kf: freezing point depression constant

b: molality

The mass of the solvent (benzene) is:

The moles of solute (naphtalene) are:

The molality of naphtalene is:

ΔTf = Kf . b

ΔTf = (4.90°C/m) . 0.972m = 4.76°C

The melting point of the solution is:

5.50°C - 4.76°C = 0.74°C

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.