The balanced combustion reaction of propane, C₃H₈, is
C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O
Molar mass of propane: 44 g/mol
Moles of propane = 42 g * (1 mol/44g) = 0.9545 mol propane
Molar mass of oxygen: 32 g/mol
Moles of oxygen = 115 g * (1 mol/32 g) = 3.594 mol oxygen
Moles of oxygen needed to completely react propane:
0.9545 mol propane * (5 mol O₂/1 mol propane) = 4.7725 mol oxygen
Since the available oxygen is only 3.594 moles and propane needs 4.7725 moles, that means oxygen is our limiting reactant. We base the amount of water produced here.
Molar mass of water: 18 g/mol
Mass of water produced = 3.594 mol O₂ * (4 mol H₂O/5 mol O₂) * (18 g/mol)
Mass of water produced = 258.768 grams
Answer:
B There are two grams of hydrogen for each gram of carbon in this compound.
Explanation:
The second option is a wrong interpretation of this chemical representation of formaldehyde.
Formaldehyde is an organic compound with the formula CH₂O.
As this is the simplest formula of the compound, it is the empirical formula. Also, the formula is the actual one for the compound and it is the molecular formula.
Chemically, the formula shows 1 mole of carbon, 2 moles of H and 1 mole of oxygen in the compound.
- A mole of a substance is more a less a unit of measurement in chemistry and it is the amount of substance that contains the avogadro's number of particles.
This ratio is not the mass of chemical species in the compound. You cannot tell the mass of elements in a compound by merely looking at the formula.
The answer is B.
This is the definition of La Châtelier's principle: <span>When the equilibrium of a system is disturbed, the system makes adjustments to restore equilibrium.</span>
