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assuming the nitrogen milecule is moving with rms velcoty at 400k the debroglie wavelft of nitrogen is close to

User Nick Sharp
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1 Answer

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Final answer:

The de Broglie wavelength of a nitrogen molecule can be determined using its rms velocity and the de Broglie relation, which involves Planck's constant and the particle's momentum.

Step-by-step explanation:

The de Broglie wavelength
(\(\lambda\)) of a particle is given by the de Broglie wavelength formula:


\[\lambda = (h)/(p)\]

where:


\(\lambda\) is the de Broglie wavelength,


\(h\) is Planck's constant
(\(6.626 * 10^(-34) \, \text{m}^2 \cdot \text{kg} / \text{s}\)),


\(p\) is the momentum of the particle.

The momentum
(\(p\)) of a particle is given by:


\[p = m \cdot v\]

where:


\(m\) is the mass of the particle,


\(v\) is the velocity of the particle.

For a nitrogen molecule
(\(N_2\)), the mass
(\(m\)) is the total mass of the molecule. The root mean square velocity
(\(v_{\text{rms}}\)) is related to the velocity of the particles in a gas, and it is given by:


\[v_{\text{rms}} = \sqrt{(3 \cdot k \cdot T)/(m)}\]

where:


\(k\) is the Boltzmann constant
(\(1.381 * 10^(-23) \, \text{J/K}\)),


\(T\) is the temperature in kelvin.

Let's calculate it for nitrogen
(\(N_2\)) at a temperature of 400 K.

First, we find
\(v_{\text{rms}}\):


\[v_{\text{rms}} = \sqrt{(3 \cdot k \cdot T)/(m)}\]

Substitute the values:


\[v_{\text{rms}} = \sqrt{\frac{3 \cdot (1.381 * 10^(-23) \, \text{J/K}) \cdot 400 \, \text{K}}{m_(N_2)}}\]

The molar mass of
\(N_2\) is approximately
\(28.02 \, \text{g/mol}\), so the mass of one nitrogen molecule
(\(m_(N_2)\)) is \(28.02 * 10^(-3) \, \text{kg/mol}\).

Now, calculate
\(v_{\text{rms}}\), and then use it to find the momentum
\(p\) and finally the de Broglie wavelength
\(\lambda\).

User Leo Fabrikant
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