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What volume of nitrogen dioxide is formed at 705 torr and 28.2°C by reacting 1.95 cm3 of copper (d = 8.95 g/cm) with 1.50 L of nitric acid 2.53 M? Cu(s) + 4 HNO3 (aq) → Cu(NO3)2(aq) + 2NO2(g) + 2 H2O1. 4.26 L 2. 25.4 L3. 14.7 L 4. 50.8 L 5. 7.35 L

User BurnsBA
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Answer:

The volume of nitrogen dioxide formed is 14.7 L

Step-by-step explanation:

Step 1: Data given

Pressure = 708 torr

Temperature = 28.2 °C

volume of copper = 1.95 cm³ of copper

Density of copper = 8.95 g/cm

Volume of 2.53 M nitric acid = 1.50 L

Step 2: The balanced equation

Cu(s) + 4 HNO3 (aq) → Cu(NO3)2(aq) + 2NO2(g) + 2 H2O

Step 3: Calculate the moles of HNO3

Moles HNO3 = Molarity * volume

Moles HNO3 = 2.53 M * 1.50 L

Moles HNO3 = 3.795 moles

Step 4: Calculate mass of copper

Mass = density * volume

Mass coper = 8.95 g/cm³ * 1.95 cm³

Mass of copper = 17.4525 grams copper

Step 5: Calculate moles Cu

Moles Cu = mass of Cu / molar mass Cu

Moles Cu = 17.4525g / 63.546 g/mol

Moles Cu = 0.27464 moles

Step 6: Calculate limiting reactant

For 1 mole of copper, we need 4 moles of HNO3 to produce 2 moles of NO2

Cu is the limiting reactant. It will completely be consumed (0.27464 moles).

HNO3 is in excess. There will 4*0.27464 = 1.09856 moles be consumed.

There will remain 3.795 - 1.09856 = 2.69644 moles

Step 7: Calculate moles of NO2

For 1 mole of copper, we need 4 moles of HNO3 to produce 2 moles of NO2

For 1 moles 0.27464 moles of Cu, there will be produced 2* 0.27464 = 0.54928 moles of NO2

Step 8: Calculate volume of NO2

p*V = n*R*T

⇒ p = the pressure = 705 torr = 705/760 = 0.927632 atm

⇒ V = the volume of NO2 = TO BE DETERMINED

⇒ n = the moles of NO2 = 0.54928 moles

⇒ R = the gas constant = 0.08206 L*atm/K*mol

⇒ T = the temperature = 28.2 °C = 301.35 Kelvin

V = (nRT)/p

V = (0.54928 *0.08206 * 301.35)/0.927632

V = 14.7 L

The volume of nitrogen dioxide formed is 14.7 L

User Egor Pavlikhin
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