Natasha was trying to identify 452.1 g of an unknown non- electrolyte sample. Given the limited instruments in their laboratory, she decided to mix the sample into 500.0 mL of water to determine the sample's effect on its boiling point and freezing point. The table shows the data she collected for the experiment (Kb= 0.512 °C/m and Kf= 1.86 OC/m) Trial 1 (°C) Trial 2 (°C) Trial 3 (°C) Mean (°C) Boiling point 104.20 103.80 104.10 104.03 Freezing point -14.71 -14.65 -14.63 -14.66 What is the molecular weight of the unknown sample? 229.4 g/mol 28.69 g/mol 57.23 g/mol 114.5 g/mol

Natasha was trying to identify 452.1 g of an unknown non- electrolyte sample. Given the limited instruments in their laboratory, she decided to mix the sample into 500.0 mL of water to determine the sample's effect on its boiling point and freezing point. The table shows the data she collected for the experiment (Kb= 0.512 °C/m and Kf= 1.86 OC/m) Trial 1 (°C) Trial 2 (°C) Trial 3 (°C) Mean (°C) Boiling point 104.20 103.80 104.10 104.03 Freezing point -14.71 -14.65 -14.63 -14.66 What is the molecular weight of the unknown sample? 229.4 g/mol 28.69 g/mol 57.23 g/mol 114.5 g/mol

Chemistry: Matter and Change

1st Edition

ISBN:9780078746376

Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl Wistrom

Publisher:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl Wistrom

Chapter14: Mixtures And Solutions

Section: Chapter Questions

Problem 106A: Which solute has the greatest effect on the boiling pointof 1.00 kg of water: 50.0 g of strontium...

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Part II. Determination of molecular weight for ethyl alcohol Freezing point, °C DTf Mass of solute, g mass of solvent, kg Calculated molecular weight, g/mol -2.30 0C ΔTf = T0f – Tf 0.0 °C -(-2.30 °C) = 2.30 0C 6.202 g 0.1kg Click or tap here to enter text.
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