The Empirical Formula Of A Compound Is $CH_2$. If The Molar Mass Of This Compound Is About $70 \, \text{g}$, What Is Its Molecular Formula?
Introduction
In chemistry, understanding the empirical and molecular formulas of a compound is crucial for determining its composition and properties. The empirical formula represents the simplest whole-number ratio of atoms of each element present in a compound, while the molecular formula shows the actual number of atoms of each element in a molecule of the compound. In this article, we will explore how to determine the molecular formula of a compound given its empirical formula and molar mass.
Understanding Empirical and Molecular Formulas
The empirical formula of a compound is a representation of the simplest whole-number ratio of atoms of each element present in the compound. For example, the empirical formula of glucose is $CH_2O$. However, the molecular formula of glucose is $C_6H_{12}O_6$, which shows the actual number of atoms of each element in a molecule of glucose.
Calculating the Molecular Formula
To calculate the molecular formula of a compound, we need to know its empirical formula and molar mass. The empirical formula mass is the sum of the atomic masses of the elements present in the empirical formula. For the empirical formula $CH_2$, the empirical formula mass is:
Determining the Molecular Formula
Given that the molar mass of the compound is about $70 , \text{g}$, we can use the empirical formula mass to determine the molecular formula. We can start by dividing the molar mass of the compound by the empirical formula mass:
Calculating the Molecular Formula
Now that we have the multiplication factor, we can calculate the molecular formula by multiplying the empirical formula by the multiplication factor:
Conclusion
In conclusion, the molecular formula of a compound can be determined by knowing its empirical formula and molar mass. By dividing the molar mass of the compound by the empirical formula mass, we can determine the multiplication factor, which can then be used to calculate the molecular formula by multiplying the empirical formula by the multiplication factor. In this article, we have seen how to determine the molecular formula of a compound given its empirical formula and molar mass.
Frequently Asked Questions
Q: What is the difference between the empirical and molecular formulas of a compound?
A: The empirical formula represents the simplest whole-number ratio of atoms of each element present in a compound, while the molecular formula shows the actual number of atoms of each element in a molecule of the compound.
Q: How do I determine the molecular formula of a compound given its empirical formula and molar mass?
A: To determine the molecular formula, divide the molar mass of the compound by the empirical formula mass to get the multiplication factor, and then multiply the empirical formula by the multiplication factor.
Q: What is the significance of the multiplication factor in determining the molecular formula?
A: The multiplication factor is used to calculate the molecular formula by multiplying the empirical formula by the multiplication factor.
Q: Can the molecular formula of a compound be determined without knowing its empirical formula?
A: No, the molecular formula of a compound cannot be determined without knowing its empirical formula and molar mass.
References
- [1] Petrucci, R. H., Harwood, W. S., & Herring, F. G. (2016). General Chemistry: Principles and Modern Applications. Pearson Education.
- [2] Atkins, P. W., & De Paula, J. (2010). Physical Chemistry. Oxford University Press.
- [3] Chang, R. (2010). Chemistry. McGraw-Hill Education.
Further Reading
- [1] Empirical and Molecular Formulas: A Guide to Understanding Chemical Composition
- [2] Calculating the Molecular Formula of a Compound: A Step-by-Step Guide
- [3] The Importance of Empirical and Molecular Formulas in Chemistry
Introduction
In our previous article, we discussed how to determine the molecular formula of a compound given its empirical formula and molar mass. In this article, we will answer some frequently asked questions related to empirical and molecular formulas.
Q&A
Q: What is the difference between the empirical and molecular formulas of a compound?
A: The empirical formula represents the simplest whole-number ratio of atoms of each element present in a compound, while the molecular formula shows the actual number of atoms of each element in a molecule of the compound.
Q: How do I determine the molecular formula of a compound given its empirical formula and molar mass?
A: To determine the molecular formula, divide the molar mass of the compound by the empirical formula mass to get the multiplication factor, and then multiply the empirical formula by the multiplication factor.
Q: What is the significance of the multiplication factor in determining the molecular formula?
A: The multiplication factor is used to calculate the molecular formula by multiplying the empirical formula by the multiplication factor.
Q: Can the molecular formula of a compound be determined without knowing its empirical formula?
A: No, the molecular formula of a compound cannot be determined without knowing its empirical formula and molar mass.
Q: How do I know if the empirical formula I have is correct?
A: To verify the empirical formula, calculate the empirical formula mass and compare it with the molar mass of the compound. If the empirical formula mass is equal to the molar mass, then the empirical formula is correct.
Q: What if the empirical formula mass is not equal to the molar mass?
A: If the empirical formula mass is not equal to the molar mass, then the empirical formula is not correct. In this case, you need to re-examine the empirical formula and recalculate the empirical formula mass.
Q: Can the molecular formula of a compound be determined if the empirical formula is not known?
A: No, the molecular formula of a compound cannot be determined if the empirical formula is not known.
Q: How do I determine the empirical formula of a compound?
A: To determine the empirical formula, you need to know the molar mass of the compound and the atomic masses of the elements present in the compound. You can then use the molar mass to calculate the empirical formula mass and determine the simplest whole-number ratio of atoms of each element present in the compound.
Q: What is the difference between the empirical formula and the molecular formula of a compound in terms of the number of atoms?
A: The empirical formula shows the simplest whole-number ratio of atoms of each element present in a compound, while the molecular formula shows the actual number of atoms of each element in a molecule of the compound.
Q: Can the molecular formula of a compound be determined if the molar mass is not known?
A: No, the molecular formula of a compound cannot be determined if the molar mass is not known.
Q: How do I determine the molar mass of a compound?
A: To determine the molar mass of a compound, you need to know the atomic masses of the elements present in the compound and the number of atoms of each element present in the compound. You can then use the atomic masses to calculate the molar mass.
Conclusion
In conclusion, empirical and molecular formulas are important concepts in chemistry that help us understand the composition and properties of compounds. By answering these frequently asked questions, we hope to have provided a better understanding of these concepts and how to apply them in practice.
Further Reading
- [1] Empirical and Molecular Formulas: A Guide to Understanding Chemical Composition
- [2] Calculating the Molecular Formula of a Compound: A Step-by-Step Guide
- [3] The Importance of Empirical and Molecular Formulas in Chemistry
References
- [1] Petrucci, R. H., Harwood, W. S., & Herring, F. G. (2016). General Chemistry: Principles and Modern Applications. Pearson Education.
- [2] Atkins, P. W., & De Paula, J. (2010). Physical Chemistry. Oxford University Press.
- [3] Chang, R. (2010). Chemistry. McGraw-Hill Education.