The molar enthalpy of combustion, fuel value and percentage of hydrogen by mass of the given hydrocarbons is to be calculated; also the relationship between hydrogen content and the fuel value is to be determined. Concept Introduction: The molar enthalpy change of the given reaction is calculated by the difference of sum of the enthalpy change of products and reactants. The fuel value of the given hydrocarbons is calculated by dividing its molar enthalpy of combustion by the molar mass. The percentage hydrogen content of the hydrocarbon is calculated by dividing the molar mass of hydrogen in the given hydrocarbon by the molar mass of hydrocarbon and multiplying the resultant value by 100 . (a) To determine: The molar enthalpy of combustion for the given hydrocarbons.
The molar enthalpy of combustion, fuel value and percentage of hydrogen by mass of the given hydrocarbons is to be calculated; also the relationship between hydrogen content and the fuel value is to be determined. Concept Introduction: The molar enthalpy change of the given reaction is calculated by the difference of sum of the enthalpy change of products and reactants. The fuel value of the given hydrocarbons is calculated by dividing its molar enthalpy of combustion by the molar mass. The percentage hydrogen content of the hydrocarbon is calculated by dividing the molar mass of hydrogen in the given hydrocarbon by the molar mass of hydrocarbon and multiplying the resultant value by 100 . (a) To determine: The molar enthalpy of combustion for the given hydrocarbons.
Interpretation: The molar enthalpy of combustion, fuel value and percentage of hydrogen by mass of the given hydrocarbons is to be calculated; also the relationship between hydrogen content and the fuel value is to be determined.
Concept Introduction: The molar enthalpy change of the given reaction is calculated by the difference of sum of the enthalpy change of products and reactants.
The fuel value of the given hydrocarbons is calculated by dividing its molar enthalpy of combustion by the molar mass. The percentage hydrogen content of the hydrocarbon is calculated by dividing the molar mass of hydrogen in the given hydrocarbon by the molar mass of hydrocarbon and multiplying the resultant value by 100 .
(a)
To determine: The molar enthalpy of combustion for the given hydrocarbons.
Step 1:
Interpretation Introduction
To determine: The molar enthalpy of combustion of 1,3-butadiene.
Step 2:
Interpretation Introduction
To determine: The molar enthalpy of combustion of 1-butene.
Step 3:
Interpretation Introduction
To determine: The molar enthalpy of combustion of n-butane.
(b)
Interpretation Introduction
To determine: The fuel value of the given hydrocarbons.
Step 1:
Interpretation Introduction
To determine: The fuel value of 1,3-butadiene.
Step 2:
Interpretation Introduction
To determine: The fuel value of 1-butene.
Step 3:
Interpretation Introduction
To determine: The fuel value of n-butane.
(c)
Interpretation Introduction
To determine: The percentage of hydrogen by mass in the given hydrocarbons.
Step 1:
Interpretation Introduction
To determine: The percentage of hydrogen by mass of 1,3-butadiene.
Step 2:
Interpretation Introduction
To determine: The percentage of hydrogen by mass of 1-butene.
Step 3:
Interpretation Introduction
To determine: The percentage of hydrogen by mass of n-butane.
(d)
Interpretation Introduction
To determine: The relationship between hydrogen content and the fuel value of given hydrocarbons.
In the video, we looked at the absorbance of a certain substance and how it varies
depending on what wavelength of light we are looking at. Below is a similar scan of a
different substance. What color BEST describes how this substance will appear?
Absorbance (AU)
Violet
Blue
Green
Orange
1.2
1.0-
0.8-
0.6-
0.4-
0.2
0.0
450
500
550
600
650
700
Wavelength (nm)
violet
indigo
blue
green
yellow orange
red
Red
O Cannot tell from this information
In the above graph, what causes -450 nm wavelength of light to have a higher
absorbance than light with a -550 nm wavelength? Check all that are true.
The distance the light travels is different
The different data points are for different substances
The concentration is different at different times in the experiment
Epsilon (molar absortivity) is different at different wavelengths
5. a. Data were collected for Trial 1 to determine the molar mass of a nonvolatile solid solute when dissolved in cyclo-
hexane. Complete the table for the analysis (See Report Sheet). Record calculated values with the correct number
of significant figures.
B. Freezing Point of Cyclohexane plus
Calculation Zone
Unknown Solute
2. Mass of cyclohexane (g)
10.14
Part C.4
3. Mass of added solute (g)
0.255
C. Calculations
1. k; for cyclohexane (°C⚫ kg/mol)
20.0
2. Freezing point change, AT, (°C)
3.04
Part C.6
3. Mass of cyclohexane in solution (kg)
4. Moles of solute, total (mol)
Show calculation.
5. Mass of solute in solution, total (g)
6. Molar mass of solute (g/mol)
Show calculation.
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
The Laws of Thermodynamics, Entropy, and Gibbs Free Energy; Author: Professor Dave Explains;https://www.youtube.com/watch?v=8N1BxHgsoOw;License: Standard YouTube License, CC-BY