Calculating the Molar Mass of Aluminum Hydroxide

Oct 13, 2025 by wbrum.org 128 views

Understanding Atomic Mass and Molar Mass

The atomic mass of an element is the average mass of a single atom of that element, typically expressed in units of atomic mass units (amu) or grams per mole (g/mol). The atomic mass of hydrogen is 1.01 amu or 1.01 g/mol. On the other hand, the molar mass of a compound is the sum of the atomic masses of its constituent atoms, expressed in units of g/mol.

Calculating the Molar Mass of Aluminum Hydroxide

To calculate the molar mass of aluminum hydroxide (Al(OH)3), we need to sum the atomic masses of its constituent atoms: aluminum (Al), oxygen (O), and hydrogen (H). The atomic masses of these elements are:

Aluminum (Al): 26.98 g/mol
Oxygen (O): 16.00 g/mol
Hydrogen (H): 1.01 g/mol

The formula for aluminum hydroxide is Al(OH)3, which means it consists of one aluminum atom, three oxygen atoms, and three hydrogen atoms. Therefore, the molar mass of aluminum hydroxide is:

Molar mass of Al(OH)3 = (1 x 26.98) + (3 x 16.00) + (3 x 1.01) = 26.98 + 48.00 + 3.03 = 78.01 g/mol

Determining the Mass of Hydrogen in One Mole of Aluminum Hydroxide

Now that we have the molar mass of aluminum hydroxide, we can determine the mass of hydrogen in one mole of the compound. Since the formula for aluminum hydroxide is Al(OH)3, it contains three hydrogen atoms per molecule. Therefore, the mass of hydrogen in one mole of aluminum hydroxide is:

Mass of hydrogen in one mole of Al(OH)3 = (3 x 1.01) g = 3.03 g

Conclusion

In conclusion, the mass of hydrogen in one mole of aluminum hydroxide (Al(OH)3) is 3.03 g. This is because the formula for aluminum hydroxide contains three hydrogen atoms per molecule, and the atomic mass of hydrogen is 1.01 g/mol.

Answer

The correct answer is C. 3.01 g.

Key Takeaways

The atomic mass of hydrogen is 1.01 amu or 1.01 g/mol.
The molar mass of a compound is the sum of the atomic masses of its constituent atoms, expressed in units of g/mol.
The molar mass of aluminum hydroxide (Al(OH)3) is 78.01 g/mol.
The mass of hydrogen in one mole of aluminum hydroxide is 3.03 g.
The Atomic Mass of Hydrogen in Aluminum Hydroxide: Q&A =====================================================

Frequently Asked Questions

Q: What is the atomic mass of hydrogen?

A: The atomic mass of hydrogen is 1.01 amu or 1.01 g/mol.

Q: What is the molar mass of aluminum hydroxide (Al(OH)3)?

A: The molar mass of aluminum hydroxide (Al(OH)3) is 78.01 g/mol.

Q: How many hydrogen atoms are present in one molecule of aluminum hydroxide?

A: One molecule of aluminum hydroxide (Al(OH)3) contains three hydrogen atoms.

Q: What is the mass of hydrogen in one mole of aluminum hydroxide?

A: The mass of hydrogen in one mole of aluminum hydroxide is 3.03 g.

Q: Why is the mass of hydrogen in one mole of aluminum hydroxide not 1.01 g?

A: The mass of hydrogen in one mole of aluminum hydroxide is not 1.01 g because there are three hydrogen atoms present in one molecule of aluminum hydroxide. Therefore, the total mass of hydrogen in one mole of aluminum hydroxide is 3 x 1.01 = 3.03 g.

Q: What is the relationship between atomic mass and molar mass?

A: The molar mass of a compound is the sum of the atomic masses of its constituent atoms, expressed in units of g/mol.

Q: How can I calculate the molar mass of a compound?

A: To calculate the molar mass of a compound, you need to sum the atomic masses of its constituent atoms. For example, to calculate the molar mass of aluminum hydroxide (Al(OH)3), you need to sum the atomic masses of aluminum (Al), oxygen (O), and hydrogen (H).

Q: What is the significance of the molar mass of a compound?

A: The molar mass of a compound is significant because it allows us to calculate the mass of a substance in a given amount of the compound. For example, if we know the molar mass of aluminum hydroxide (Al(OH)3) and the number of moles of the compound, we can calculate the mass of the compound.

Q: How can I apply the concept of atomic mass and molar mass in real-life situations?

A: The concept of atomic mass and molar mass can be applied in various real-life situations, such as:

Calculating the mass of a substance in a given amount of a compound
Determining the number of moles of a substance in a given amount of a compound
Calculating the mass of a substance in a mixture of compounds
Determining the composition of a mixture of compounds

Conclusion

In conclusion, the atomic mass of hydrogen is 1.01 amu or 1.01 g/mol, and the molar mass of aluminum hydroxide (Al(OH)3) is 78.01 g/mol. The mass of hydrogen in one mole of aluminum hydroxide is 3.03 g. Understanding the concept of atomic mass and molar mass is essential in various real-life situations, such as calculating the mass of a substance in a given amount of a compound and determining the composition of a mixture of compounds.

Key Takeaways

The atomic mass of hydrogen is 1.01 amu or 1.01 g/mol.
The molar mass of a compound is the sum of the atomic masses of its constituent atoms, expressed in units of g/mol.
The mass of hydrogen in one mole of aluminum hydroxide is 3.03 g.
Understanding the concept of atomic mass and molar mass is essential in various real-life situations.