An electric bulb of volume `250 cm^(3)` was sealed off during manufacture at a pressure of `10^(-3)` mm of Hg at `27^(@) C`. Find the number of molecules in the bulb. Given, Boltzmann constant `=1.38 xx 10^(-16) "erg molecule"^(-1) ^(@)C^(-1)`.

Explanation

To find the number of molecules in the electric bulb, we will use the ideal gas equation and the given data. Here are the steps to solve the problem:

### Step 1: Convert the given pressure to CGS units
The pressure is given as \(10^{-3}\) mm of Hg. We need to convert this to dynes/cm² (CGS unit).

1 mm of Hg = 980 dynes/cm²

So,
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