
Concept explainers
(a)
Interpretation:
The molar mass of the solute is to be calculated.
Concept introduction:
The boiling point of the substance is the temperature at which the vapor pressure of the liquid becomes equal to the atmospheric pressure and the liquid changes into a vapor. Liquids can change into vapors at temperatures below the boiling point through evaporation. It is the process that occurs on the liquid surface due to which it changes into vapors. It is a colligative property because it depends on the number of moles of solute particles that are present in the substance.
The formula to calculate the change in boiling point is as follows:
Here,
(a)

Answer to Problem 13.135P
Explanation of Solution
The formula to calculate the change in boiling point is as follows:
Substitute
The solute is a nonvolatile non-electrolyte so its van’t Hoff factor is 1.
Rearrange equation (1) to calculate the molarity of the solution as follows:
Substitute 1 for
The density of the solution is calculated as follows:
Rearrange equation (4) to calculate the mass of the solution as follows:
Substitute
The formula to calculate the molality of the solution is as follows:
Rearrange equation (6) to calculate the moles of solute as follows:
Substitute
The formula to calculate the number of moles is as follows:
Rearrange equation (8) to calculate the molar mass as follows:
Substitute
Boiling point elevation is a colligative property as it depends on the number of moles of solute.
(b)
Interpretation:
The molar mass of the solute is to be calculated.
Concept introduction:
The boiling point of the substance is the temperature at which the vapor pressure of the liquid becomes equal to the atmospheric pressure and the liquid changes into a vapor. Liquids can change into vapors at temperatures below the boiling point through evaporation. It is the process that occurs on the liquid surface due to which it changes into vapors. It is a colligative property because it depends on the number of moles of solute particles that are present in the substance.
The formula to calculate the change in boiling point is as follows:
Here,
(b)

Answer to Problem 13.135P
Explanation of Solution
The solute is ionic with general formula
Substitute 3 for
Substitute
Substitute
Boiling point elevation depends on the moles of solute and therefore it is a colligative property.
(c)
Interpretation:
The difference between the actual formula mass and that calculated from the boiling point elevation is to be explained.
Concept introduction:
The boiling point of the substance is the temperature at which the vapor pressure of the liquid becomes equal to the atmospheric pressure and the liquid changes into a vapor. Liquids can change into vapors at temperatures below the boiling point through evaporation. It is the process that occurs on the liquid surface due to which it changes into vapors. It is a colligative property because it depends on the number of moles of solute particles that are present in the substance.
(c)

Answer to Problem 13.135P
The actual molar mass of
Explanation of Solution
The molar mass of
Boiling point elevation is a colligative property as it depends on the number of moles of solute.
(d)
Interpretation:
The van’t Hoff factor for the solution is to be calculated.
Concept introduction:
The formula to relate the elevation in boiling point and van’t Hoff factor is as follows:
Here,
(d)

Answer to Problem 13.135P
2.4 is the van’t Hoff factor.
Explanation of Solution
Substitute
Substitute
Rearrange equation (1) to calculate the van’t Hoff factor is as follows:
Substitute
The van’t Hoff factor for the solution is 2.4.
Want to see more full solutions like this?
Chapter 13 Solutions
Chemistry: The Molecular Nature of Matter and Change
- 5. Propose a Synthesis for the molecule below. You may use any starting materials containing 6 carbons or less (reagents that aren't incorporated into the final molecule such as PhзP do not count towards this total, and the starting material can have whatever non-carbon functional groups you want), and any of the reactions you have learned so far in organic chemistry I, II, and III. Your final answer should show each step separately, with intermediates and conditions clearly drawn. H3C CH3arrow_forwardState the name and condensed formula of isooxazole obtained by reacting acetylacetone and hydroxylamine.arrow_forwardState the name and condensed formula of the isothiazole obtained by reacting acetylacetone and thiosemicarbazide.arrow_forward
- Provide the semi-developed formula of isooxazole obtained by reacting acetylacetone and hydroxylamine.arrow_forwardGiven a 1,3-dicarbonyl compound (R1-CO-CH2-CO-R2), indicate the formula of the compound obtaineda) if I add hydroxylamine (NH2OH) to give an isooxazole.b) if I add thiosemicarbazide (NH2-CO-NH-NH2) to give an isothiazole.arrow_forwardAn orange laser has a wavelength of 610 nm. What is the energy of this light?arrow_forward
- The molar absorptivity of a protein in water at 280 nm can be estimated within ~5-10% from its content of the amino acids tyrosine and tryptophan and from the number of disulfide linkages (R-S-S-R) between cysteine residues: Ε280 nm (M-1 cm-1) ≈ 5500 nTrp + 1490 nTyr + 125 nS-S where nTrp is the number of tryptophans, nTyr is the number of tyrosines, and nS-S is the number of disulfide linkages. The protein human serum transferrin has 678 amino acids including 8 tryptophans, 26 tyrosines, and 19 disulfide linkages. The molecular mass of the most dominant for is 79550. Predict the molar absorptivity of transferrin. Predict the absorbance of a solution that’s 1.000 g/L transferrin in a 1.000-cm-pathlength cuvet. Estimate the g/L of a transferrin solution with an absorbance of 1.50 at 280 nm.arrow_forwardIn GC, what order will the following molecules elute from the column? CH3OCH3, CH3CH2OH, C3H8, C4H10arrow_forwardBeer’s Law is A = εbc, where A is absorbance, ε is the molar absorptivity (which is specific to the compound and wavelength in the measurement), and c is concentration. The absorbance of a 2.31 × 10-5 M solution of a compound is 0.822 at a wavelength of 266 nm in a 1.00-cm cell. Calculate the molar absorptivity at 266 nm.arrow_forward
- How to calculate % of unknown solution using line of best fit y=0.1227x + 0.0292 (y=2.244)arrow_forwardGiven a 1,3-dicarbonyl compound, state the (condensed) formula of the compound obtaineda) if I add hydroxylamine (NH2OH) to give an isooxazole.b) if I add thiosemicarbazide (NH2-CO-NH-NH2) to give an isothiazole.arrow_forwardComplete the following acid-base reactions and predict the direction of equilibrium for each. Justify your prediction by citing pK values for the acid and conjugate acid in each equilibrium. (a) (b) NHs (c) O₂N NH NH OH H₁PO₁arrow_forward
- ChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage LearningChemistryChemistryISBN:9781259911156Author:Raymond Chang Dr., Jason Overby ProfessorPublisher:McGraw-Hill EducationPrinciples of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning
- Organic ChemistryChemistryISBN:9780078021558Author:Janice Gorzynski Smith Dr.Publisher:McGraw-Hill EducationChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningElementary Principles of Chemical Processes, Bind...ChemistryISBN:9781118431221Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. BullardPublisher:WILEY





