Answer:
-753kJ of energy are involved
Explanation:
Based on the reaction:
Fe₂O₃(s) + 2 Al(s) → Al₂O₃(s) + 2 Fe(s) ΔH°rxn = -852 kJ
<em>When 2 moles of Fe are produced, there are released -852kJ.</em>
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98.7g of Fe are:
98.7g Fe × (1mol / 55.845g) = 1.767 moles of Fe
If 2 moles of Fe are producen when -852 kJ of energy are involved, 1.767 moles of Fe envolved:
1.767mol × (-852kJ / 2mol Fe) = <em>-753kJ of energy are involved</em>
Answer:
5.01%
Explanation:
Density of vinegar = mass/volume
Mass of 10.00 mL = density x volume
= 1.006 x 10 = 10.06 g
From the equation of reaction:

1 mole pf CH3COOH requires 1 mole of NaOH for neutralization.
mole of NaOH = molarity x volume
= 0.5062 x 0.01658
= 0.008392796 mole
0.008392796 mole of NaOH will therefore require 0.008392796 mole of CH3COOH.
mass of CH3COOH = mole x molar mass
= 0.008392796 x 60.052
= 0.504 g
Percentage by mass of acetic acid in the vinegar = 0.504/10.06 x 100%
= 5.01%
The percent by mass of acetic acid in the vinegar is 5.01%