# Refractive index of a gas (1 Viewer)

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#### Aeon

Dependence of refractive index on pressure

1. The problem statement, all variables and given/known data
Show that, in a gas (for which the refractive index is close to 1), the refractive index depends on the pressure as $$n_r = 1+ K\times p$$, and find the value of K.

2. Relevant equations

$$n_r = 1+ K\times p$$
Clausius-Mossotti equation: $$\frac{\epsilon_r - 1}{\epsilon_r + 2} = \frac{\rho N_a \alpha}{3M\epsilon_0}$$
$$\alpha^'\ = \frac{\alpha}{4\pi \epsilon_0}$$
$$n_r = \epsilon_r^{1/2}$$
3. The attempt at a solution

I wish I could do organic chemistry...

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