At room temperature, the following reaction proceeds nearly to completion:
`2NO+O_(2)to2NO_(2)toN_(2)O_(4)`
The dimer, `N_(2)O_(4)`, solidfies at `262 K`. A `250 mL` flask and a `100 mL` flask are separated by a stopcock. At `300 K`, the nitric oxide in the larger flask exerts a pressure of `1.053 atm` and the smaller one contains oxygen at `0.789 atm`. The gase are mixed by opening the stopcock and after the end of the reaction the flasks are cooled to `220 K`. Neglecting the vapour pressure of the dimer, find out the pressure and composition of the gas remaining at `220 K`. (Assume the gases to behave ideally)

Explanation

To solve the problem step-by-step, we will follow the outlined approach based on the information given in the question.

### Step 1: Calculate the moles of NO and O2 in their respective flasks.

**For NO in the 250 mL flask:**
- Given: Pressure (P) = 1.053 atm, Volume (V) = 250 mL = 0.250 L, Temperature (T) = 300 K
- Using the ideal gas equation: \( PV = nRT \)

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