Concept explainers
Reference Section 5-2 to find the
Interpretation: The atomic masses, relative abundance, the average mass and the number of
Concept introduction: The number of moles is defined as the ratio of mass with the molecular mass of an element. The mass of an element is the amount of the substance present in an element. The mass is calculated by using number of moles in an element.
To determine: The atomic masses, relative abundance, the average mass and the number of
Answer to Problem 23Q
The numbers of
The numbers of
The average mass of a carbon atom is
The mass of one mole of carbon in grams is
Explanation of Solution
Given
Total number of atoms in a sample of natural carbon is
The composition of
The composition of
The conversion of
The number of
For
Substitute the value of percentage composition of
For
Substitute the value of percentage composition of
Mass of
Mass of
Total mass of carbon atoms is calculated by using mass of
Therefore the average mass of carbon atoms is calculated by using an expression,
Substitute the value of total mass of carbon atoms and number of atoms in the above expression, the average mass is calculated.
Hence, the average mass of a carbon atom is
When the total number of atoms is
The number of
For
Substitute the value of percentage composition of
For
Substitute the value of percentage composition of
Total mass of carbon atoms is calculated by using mass of
Therefore the average mass of carbon atoms is calculated by using an expression,
Substitute the value of total mass of carbon atoms and number of atoms in the above expression, the average mass is calculated.
Hence, the average mass of a carbon atom is
When the mass of carbon is
One mole of substance contains
The mass of
Therefore, mass of one mole of carbon in grams is calculated by using the given expression,
Hence, the mass of one mole of carbon in grams is
The numbers of
The numbers of
The average mass of a carbon atom is
The mass of one mole of carbon in grams is
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Chapter 5 Solutions
Chemistry: An Atoms First Approach
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