The given question is incomplete, the complete question is:
A reaction between liquid reactants takes place at 10.0 °c in a sealed, evacuated vessel with a measured volume of 35.0 L. Measurements show that the reaction produced 28. g of dinitrogen difluoride gas. Calculate the pressure of dinitrogen difluoride gas in the reaction vessel after the reaction. You may ignore the volume of the liquid reactants. Round your answer to 2 significant digits. pressure:atm
Answer:
The correct answer is 0.28 atm.
Explanation:
The temperature mentioned in the given reaction is 10 degree C, which after conversion becomes 283 Kelvin (273+10 = 283K).
The volume mentioned in the reaction is 35 Liters.
The reaction produced 28 grams of dinitrogen difluoride gas (N2F2). The n or the no of moles of the gas can be determined with the help of the formula:
moles of N2F2 = mass/molar mass
= 28/66 (molar mass of N2F2 is 66 g/mol)
= 0.424
The pressure of the gas can be determined by using the equation of the ideal gas law, that is, PV = nRT
P * 35 = 0.424 * 0.0821 * 283
P = 0.28 atm
Answer:
0.0010m SO₄²⁻
Explanation:
The freezing point depression due the addition of a solute into a pure solvent follows the equation:
ΔT = Kf×m×i (1)
<em>Where ΔT are °C that freezing point decreases (273.15K - 272.47K = 0.68K = 0.68°C). Kf is the constant of freezing point depression (1.86°C/m), m is molality of the solution (0.1778m) and i is Van't Hoff factor.</em>
Van't Hoff factor could be understood as in how many one mole of the solute (sulfuric acid, H₂SO₄), is dissociated.
H₂SO₄ dissociates as follows:
H₂SO₄ → HSO₄⁻ + H⁺
HSO₄⁻ ⇄ SO₄²⁻ + H⁺
<em>Not all HSO₄⁻ dissociates.</em>
1 Mole of H₂SO₄ dissociates in 1 mole of H⁺+ 1 mole of HSO₄⁻ + X moles of SO₄²⁻= 2 + X
Replacing in (1):
0.68°C = 1.86°C/m×0.1778m×i
2.056 = i
Moles of SO₄²⁻ are 2.056 - 2 = 0.056moles SO₄²⁻.
If 1 mole has a concentration of 0.1778m, 0.056moles are:
0.056moles ₓ (0.1778m / 1mole) =
<h3>0.0010m SO₄²⁻</h3>
