Answer : The pressure in the flask after reaction complete is, 2.4 atm
Explanation :
To calculate the pressure in the flask after reaction is complete we are using ideal gas equation.

where,
P = final pressure in the flask = ?
R = gas constant = 0.0821 L.atm/mol.K
T = temperature = 
V = volume = 4.0 L
= moles of
= 0.20 mol
= moles of
= 0.20 mol
Now put all the given values in the above expression, we get:


Thus, the pressure in the flask after reaction complete is, 2.4 atm
<span>When two or more substances are mixed together but not chemically joined they are called as mixtures. Therefore, it is only a physical change taking place.
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I hope this helps you! Good luck :)
C sounds like the right answer in this question
Some of the solutions exhibit colligative properties. These properties depend on the amount of
solute dissolved in a solvent. These properties include freezing point depression, boiling
point elevation, osmotic pressure and vapor pressure lowering. From the given choices, the correct answer is the first option. Pure water will have the lowest boiling point because there are no solute particles to change the boiling point of water while other options will have an elevated boiling point because of the solute.
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