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Atomicity given Molar Heat Capacity at Constant Volume of Non-Linear Molecule Calculator

Atomicity Formula:

\[ N = \frac{\left(\frac{C_v}{[R]}\right) + 3}{3} \]

J/(K·mol)

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1. What is Atomicity?

Definition: Atomicity is defined as the total number of atoms present in a molecule or element.

Purpose: This calculator determines the atomicity of a non-linear molecule based on its molar heat capacity at constant volume.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ N = \frac{\left(\frac{C_v}{[R]}\right) + 3}{3} \]

Where:

Explanation: The formula relates the heat capacity of a non-linear molecule to its atomicity through the equipartition theorem.

3. Importance of Atomicity Calculation

Details: Knowing atomicity helps understand molecular structure, predict thermodynamic properties, and analyze molecular vibrations and rotations.

4. Using the Calculator

Tips: Enter the molar specific heat capacity at constant volume in J/(K·mol). The value must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the range of atomicity values?
A: For non-linear molecules, atomicity is always ≥ 3 (the smallest non-linear molecule is triatomic).

Q2: Why is this specific to non-linear molecules?
A: Non-linear molecules have 3 rotational degrees of freedom, while linear molecules have only 2, requiring a different formula.

Q3: How accurate is this calculation?
A: This is a classical approximation. Quantum effects become important at low temperatures where vibrational modes freeze out.

Q4: What's a typical Cv value for common molecules?
A: For example, water vapor (non-linear) has Cv ≈ 28 J/(K·mol) at room temperature.

Q5: Can I use this for linear molecules?
A: No, linear molecules require a different formula accounting for their 2 rotational degrees of freedom.

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