Answer:
412.1kJ
Explanation:
For the reaction , from the question -
4Fe (s) + 3O₂ (g) → 2Fe₂O₃ (s)
Δ Hrxn = Δ H°f (products) - Δ H°f (reactants)
In case the compound is in its standard state , enthalphy of formation is zero
Hence ,
for the above reaction ,
ΔHrxn =( 2 * Δ H° (Fe₂O₃ )) - [ ( 4 *Δ H° Fe ) + (3 * Δ H° O₂ )]
The value for Δ H°(Fe₂O₃ ) = - 824.2kJ/mol
Δ H° Fe = 0
Δ H° O₂ = 0
Putting in the above equation ,
ΔH rxn = ( 2 * Δ H° (Fe₂O₃ )) - 0
ΔHrxn = 2× - 824.2 kJ / mol = - 1648.4 kJ/mol
- 1648.4 kJ/mol , this much heat is released by the buring of 4 mol of Fe.
Hence ,
for 1 mol of Fe ,
- 1648.4 kJ/mol / 4 = 412.1kJ
I think it is true. The formation reaction always means that the product substance is made directly and all by the elements of the reactants. And standard means under 25℃ and one atmosphere.
56 cm
because 1 cm
=1mL
2200000 mg because 1 kg = 1000 mg
2.2 km because 1000 m = 1km
"Kilo" means 1000.
1. estuary
2. shallow waters of the caribbean sea
Answer:
Option d. is correct
Explanation:
Nitromethane is an organic compound that can be used as a fuel booster in rockets. Its chemical formula is 
.
This compound is produced as a result of reaction of sodium chloroacetate with sodium nitrite in aqueous solution.
The electron-dot structure of a nitromethane molecule shows 
charge on the nitrogen.
Option d. is correct
