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Radda [10]
2 years ago
12

A solution is made by dissolving 58.125 g of sample of an unknown, nonelectrolyte compound in water. The mass of the solution is

exactly 750.0 g. The boiling point of this solution is 100.220 ∘ C . What is the molecular weight of the unknown compound?
Chemistry
1 answer:
e-lub [12.9K]2 years ago
8 0

Answer:

molecular weight (Mb) = 0.42 g/mol

Explanation:

mass sample (solute) (wb) = 58.125 g

mass sln = 750.0 g = mass solute + mass solvent

∴ solute (b) unknown nonelectrolyte compound

∴ solvent (a): water

⇒ mb = mol solute/Kg solvent (nb/wa)

boiling point:

  • ΔT = K*mb = 100.220°C ≅ 373.22 K

∴ K water = 1.86 K.Kg/mol

⇒ Mb = ? (molecular weight) (wb/nb)

⇒ mb = ΔT / K

⇒ mb = (373.22 K) / (1.86 K.Kg/mol)

⇒ mb = 200.656 mol/Kg

∴ mass solvent = 750.0 g - 58.125 g = 691.875 g = 0.692 Kg

moles solute:

⇒ nb = (200.656 mol/Kg)*(0.692 Kg) = 138.83 mol solute

molecular weight:

⇒ Mb = (58.125 g)/(138.83 mol) = 0.42 g/mol

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Explanation:

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For the condition to be valid;

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2 years ago
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coldgirl [10]

Answer: 100.


Explanation:


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2) The unit formula of C₄H₄S₂ is equal to 1 molecule.


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5) These are the calculations for each element in the molecule C₄H₄S₂.


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The ionic equation is as below

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EXPLANATION

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