×
Get Full Access to Chemistry: The Central Science - 14 Edition - Chapter 11 - Problem 11.45
Get Full Access to Chemistry: The Central Science - 14 Edition - Chapter 11 - Problem 11.45

×

# ?Ethanol $$\left(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}\right)$$ melts at $$-114^{\circ} \mathrm{C}$$ and boils at $$78^{\circ} \mathrm{C}$$. The en

ISBN: 9780134414232 1274

## Solution for problem 11.45 Chapter 11

Chemistry: The Central Science | 14th Edition

• Textbook Solutions
• 2901 Step-by-step solutions solved by professors and subject experts
• Get 24/7 help from StudySoup virtual teaching assistants

Chemistry: The Central Science | 14th Edition

4 5 1 265 Reviews
22
0
Problem 11.45

Ethanol $$\left(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}\right)$$ melts at $$-114^{\circ} \mathrm{C}$$ and boils at $$78^{\circ} \mathrm{C}$$. The enthalpy of fusion of ethanol is 5.02 kJ/mol, and its enthalpy of vaporization is 38.56 kJ/mol. The specific heats of solid and liquid ethanol are 0.97 and 2.3 J/g-K, respectively.

(a) How much heat is required to convert 42.0 g of ethanol at $$35^{\circ} \mathrm{C}$$ to the vapor phase at $$78^{\circ} \mathrm{C}$$?

(b) How much heat is required to convert the same amount of ethanol at $$-155^{\circ} \mathrm{C}$$ to the vapor phase at $$78^{\circ} \mathrm{C}$$?

Text Transcription:

(C_2H_5OH)

-114^{\circ} C

78^{\circ} C

35^{\circ} C

-155^{\circ} C

Step-by-Step Solution:

Step 1 of 5) Equations 14.12 and 14.13 can be used with any concentration units as long as the units are the same for both 3A4t and 3A40. When dealing with gases, we can use pressure as a concentration in Equations 14.12 and 14.13. This substitution follows from the fact that the ideal gas law (see Section 10.4) dictates that at constant temperature the pressure is directly proportional to the concentration (n/V). For a first-order reaction, Equation 14.12 or 14.13 can be used in several ways. Given any three of the following quantities, we can solve for the fourth: k, t, 3A40, and 3A4t. Thus, you can use these equations to determine (1) the concentration of a reactant remaining at any time after the reaction has started, (2) the time interval required for a given fraction of a sample to react, or (3) the time interval required for a reactant concentration to fall to a certain level.

Step 2 of 2

## Discover and learn what students are asking

Calculus: Early Transcendental Functions : Space Coordinates and Vectors in Space
?In Exercises 1-4, plot the points in the same three-dimensional coordinate system. (a) (5, -2, 2)

Statistics: Informed Decisions Using Data : Inference about the Difference between Two Medians: Dependent Samples
?In Problems 3–10, use the Wilcoxon matched-pairs signedranks test to test the given hypotheses at the a = 0.05 level of significance. The dependent sa

#### Related chapters

Unlock Textbook Solution

?Ethanol $$\left(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}\right)$$ melts at $$-114^{\circ} \mathrm{C}$$ and boils at $$78^{\circ} \mathrm{C}$$. The en