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Glucose, c 6 h 12 o 6 , is a good source of food energy. when it reacts with oxygen, carbon dioxide and water are formed. how many liters of co 2 are produced when 126 g of glucose completely react with oxygen? c 6 h 12 o 6 ( s ) + 6o 2 ( g ) → 6co 2 ( g ) + 6h 2 o( l ) + 673 kcal

User Omar Wagih
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1 Answer

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94.0 L if the reaction takes place under STP.

Step-by-step explanation

The molar mass of glucose C₆H₁₂O₆ is

12.01 × 6 + 1.008 × 12 + 16.00 × 16.00 = 180.16 g / mol.

126 grams of glucose will contain 126 / 180.16 = 0.69939 mol of C₆H₁₂O₆. (To avoid rounding errors, keep a couple more digits than necessary.)

6 moles of CO₂ will be produced when 1 mole of C₆H₁₂O₆ is consumed. 0.69939 moles of C₆H₁₂O₆ will give rise to 4.196 mol of CO₂.

Assuming that the reaction takes place under STP, where T = 0 °C = 273 K and P = 1 atm. Each mole of any ideal gas will occupy a volume of 22.4 liters. The 4.196 moles of CO₂ will occupy 4.196 × 22.4 = 94.0 L. (The least significant number given is 126 g, the mass of glucose. This number has three significant figures. Thus, round the result to three significant figures.)

The volume of CO₂ can be found using the ideal gas law if the condition isn't STP. For example, T = 25 °C = 297 K and P = 1.00 × 10⁵ will lead to a different volume. By the ideal gas law,

V = (n · R · T) / (P)

where

  • V is the volume of the gas,
  • n is the number of moles of gas particles,
  • R is the ideal gas constant,
  • P is the pressure on the gas,
  • T is the absolute temperature of the gas (in degrees Kelvin.)

R = 8.314 × 10³ L · Pa / (K · mol)

Taking T = 297 K and P = 1.00 × 10⁵ Pa,

V = (4.196 × 8.314 × 10³ × 297 ) / (1.00 × 10⁵ ) = 104 L.

User Thomas Mathew
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