Mass analysis of a common drying agent of organic molecules reveals that it has the empirical formula P2O5. If the molar mass is 283.89 g/mol, which molecular formula is correct?
Mass analysis of a common drying agent of organic molecules reveals that it has the empirical formula P2O5. If the molar mass is 283.89 g/mol, which molecular formula is correct?
Chemistry
10th Edition
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Chapter1: Chemical Foundations
Section: Chapter Questions
Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...
Related questions
Question
Q11

Transcribed Image Text:### Determining the Molecular Formula from Empirical Formula and Molar Mass
Mass analysis of a common drying agent of organic molecules reveals that it has the empirical formula \( P_2O_5 \). If the molar mass is 283.89 g/mol, which molecular formula is correct?
- \(\quad\) \( P_2O_5 \)
- \(\quad\) \( P_4O_{10} \)
- \(\quad\) \( P_6H_{15} \)
- \(\quad\) \( P_5O_6 \)
- \(\quad\) \( P_3O_4 \)
#### Explanation
To determine the correct molecular formula, you divide the given molar mass by the molar mass of the empirical formula \( P_2O_5 \) and then use the resulting factor to scale the subscripts in the empirical formula.
* **Step 1:** Calculate the molar mass of the empirical formula \( P_2O_5 \):
- Phosphorus (P): \( 2 \times 30.97 \) g/mol
- Oxygen (O): \( 5 \times 16.00 \) g/mol
Molar mass of \( P_2O_5 \) = \( 2 \times 30.97 \) + \( 5 \times 16.00 \)
= \( 61.94 \) + \( 80.00 \)
= \( 141.94 \) g/mol
* **Step 2:** Divide the given molar mass by the molar mass of the empirical formula:
Scaling factor = \( \frac{283.89\ g/mol}{141.94\ g/mol} \approx 2 \)
* **Step 3:** Multiply the subscripts in the empirical formula by this factor to get the molecular formula:
Molecular formula = \( P_{2 \times 2}O_{5 \times 2} \)
= \( P_4O_{10} \)
Therefore, the correct molecular formula is **\( P_4O_{10} \)**.
Expert Solution

This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 2 steps with 2 images

Knowledge Booster
Learn more about
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.Recommended textbooks for you

Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning

Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education

Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning

Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning

Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education

Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning

Organic Chemistry
Chemistry
ISBN:
9780078021558
Author:
Janice Gorzynski Smith Dr.
Publisher:
McGraw-Hill Education

Chemistry: Principles and Reactions
Chemistry
ISBN:
9781305079373
Author:
William L. Masterton, Cecile N. Hurley
Publisher:
Cengage Learning

Elementary Principles of Chemical Processes, Bind…
Chemistry
ISBN:
9781118431221
Author:
Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:
WILEY