Concept explainers
(a)
Interpretation:
The mean free paths for nitrogen and oxygen atoms are to be calculated.
Concept introduction:
The mean free path of collisions between gaseous atoms is given by the formula given below.
The average collision frequency of one atom is given by the formula,
The total number of collisions is given by the formula,
Answer to Problem 19.48E
The mean free paths for nitrogen and oxygen atoms are
Explanation of Solution
The mean free path of collisions between gaseous atoms is given by the formula given below.
Where,
•
•
•
•
Substitute the values in the equation (1) for nitrogen atom as given below.
Substitute the values in the equation (1) for oxygen atom as given below.
The mean free paths for nitrogen and oxygen atoms are
(b)
Interpretation:
The average collision frequencies for nitrogen and oxygen atoms are to be calculated.
Concept introduction:
The mean free path of collisions between gaseous atoms is given by the formula given below.
The average collision frequency of one atom is given by the formula,
The total number of collisions is given by the formula,
Answer to Problem 19.48E
The average collision frequencies for nitrogen and oxygen atoms are
Explanation of Solution
The average collision frequency of one atom is given by the formula,
Where,
•
•
•
•
•
The ratio of nitrogen to oxygen in air is
The mass of nitrogen and oxygen is
Substitute the values in the equation (2) for nitrogen atom as given below.
Substitute the values in the equation (2) for oxygen atom as given below.
The average collision frequencies for nitrogen and oxygen atoms are
(c)
Interpretation:
The total number of collisions between nitrogen and oxygen atoms is to be calculated.
Concept introduction:
The mean free path of collisions between gaseous atoms is given by the formula given below.
The average collision frequency of one atom is given by the formula,
The total number of collisions is given by the formula,
Answer to Problem 19.48E
The total number of collisions between nitrogen and oxygen atoms is
Explanation of Solution
The total number of collisions is given by the formula,
Where,
•
•
•
•
•
The ratio of nitrogen to oxygen in air is
The mass of nitrogen and oxygen is
The reduced mass is calculated as follows:
Substitute the mass of nitrogen and oxygen in above formula.
Thus, the reduced mass of nitrogen and oxygen is
Substitute the values in the equation (3) as given below.
The total number of collisions between nitrogen and oxygen atoms is
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Chapter 19 Solutions
Physical Chemistry
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