When 6.13 g of a certain molecular compound X are dissolved in 90. g of formamide (NH2COH), the freezing point of the solution is measured to be 2.1 °C. Calculate the molar mass of X. If you need any additional information on formamide, use only what you find in the ALEKS Data resource. Also, be sure your answer has a unit symbol, and is rounded to the correct number of significant digits.

321.6 g/Mol

Explanation:

mass of solvent in kilograms = 90g/1000 = 0.09 Kg

Given that;

ΔTf = Kf . m . i

Where;

Kf = freezing point constant = 4.25 °C/Kg mol

m = molality of the solution

i = Van't Hoff factor = 1 (since the substance is molecular)

ΔTf = freezing point of pure solvent - freezing point of solution

freezing point of pure solvent = 3 °C

ΔTf = 3 °C - 2.1 °C

ΔTf = 0.9  °C

0.9= 4.25 * 6.13/M/0.09 * 1

0.9= 26.0525/M * 1/0.09

0.9 = 26.0525/0.09 M

0.9 * 0.09M = 26.0525

M = 26.0525/0.9 * 0.09

M= 321.6 g/Mol

a

explanation:

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.