The problem is :2.8 grams of ethene burns in oxygen to form carbon dioxide and water
Calculate
a)the number of moles in 2.8g of ethene
b)the number of carbon dioxide(mole ratio) dioxide formed
c)the mass of carbon dioxide formed
D)the volume of carbon dioxide formed
To solve this problem, we need to use the molar masses of ethene (C2H4) and carbon dioxide (CO2) to convert between grams and moles. We also need to use the balanced chemical equation of the reaction to determine the mole ratios between ethene and carbon dioxide.
a) To calculate the number of moles in 2.8 grams of ethene, we need to divide the given mass by the molar mass of ethene.
Step 1: Determine the molar mass of ethene (C2H4).
C = 12.01 g/mol (atomic mass of carbon)
H = 1.01 g/mol (atomic mass of hydrogen)
Molar mass of C2H4 = (2 × 12.01 g/mol) + (4 × 1.01 g/mol) = 28.05 g/mol
Step 2: Calculate the number of moles.
Number of moles = Mass (g) / Molar mass (g/mol)
Number of moles = 2.8 g / 28.05 g/mol ≈ 0.09 mol
Therefore, there are approximately 0.09 moles of ethene in 2.8 grams.
b) The balanced chemical equation for the combustion of ethene is:
C2H4 + 3O2 → 2CO2 + 2H2O
According to the equation, for every 1 mole of ethene, 2 moles of carbon dioxide are formed. Therefore, the mole ratio of carbon dioxide to ethene is 2:1.
c) To find the mass of carbon dioxide formed, we can use stoichiometry and the molar mass of carbon dioxide.
Step 1: Determine the molar mass of carbon dioxide (CO2).
C = 12.01 g/mol (atomic mass of carbon)
O = 16.00 g/mol (atomic mass of oxygen)
Molar mass of CO2 = 12.01 g/mol + (2 × 16.00 g/mol) = 44.01 g/mol
Step 2: Calculate the mass of carbon dioxide formed.
Mass of CO2 = Number of moles × Molar mass
Mass of CO2 = 0.09 mol × 44.01 g/mol ≈ 3.96 g
Therefore, approximately 3.96 grams of carbon dioxide are formed.
d) To find the volume of carbon dioxide formed, we need to use the ideal gas law, assuming the ideal gas behavior at standard temperature and pressure (STP). At STP, one mole of any ideal gas occupies 22.4 liters.
Step 1: Convert the number of moles of carbon dioxide to liters.
Volume of CO2 = Number of moles × 22.4 L/mol
Volume of CO2 = 0.09 mol × 22.4 L/mol ≈ 2.02 L
Therefore, approximately 2.02 liters of carbon dioxide are formed.