In order to find the two statements, we must first define what the enthalpy of formation and the enthalpy of reaction mean.
Enthalpy of formation:
The change in enthalpy when one mole of substance is formed from its constituent elemetns at standard state.
Enthalpy of reaction:
The change in enthalpy when a reaction occurs and the reactants and products are in their standard states.
Now, we check the statements. The true ones are:
The Hrxn for C(s) + O₂(g) → CO₂(g) is the same as Hf for CO₂
This is true because the formation of carbon dioxide requires carbon and oxygen in their standard states.
The Hf for Br₂<span>(l) is 0 kJ/mol by definition.
Because the bromine is present in its standard state, the enthalpy of formation is 0.
</span><span>The Hrxn for the reaction 1.5H</span>₂<span>(g) + 0.5N</span>₂<span>(g) </span>→ <span>NH</span>₃<span>(g) is the same as the Hf for NH</span>₃<span>(g)
The reactants and products are present in their standard state, and the reaction is the same as the one occurring during the formation of ammonia.
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A collection of nerve fibers through which impulses travel between the central nervous system and other parts of the body are the nerves.
Answer:
D. 4, 3, 2.
Explanation:
Oxygen exists as the molecule O2. So it is:
4Fe + 302 ---> 2Fe2O3
Answer:
320 mmol
Explanation:
405.0 mL * 1L/1000 mL = 0.4050 L
0.79 M = 0.79 mol/L
0.79 mol/L * 0.4050 L=0.32 mol
0.32 mol * 10^3 mmol/1 mol = 320 mmol
Answer:
The volume of sample at STP is = 41.22 ml
Explanation:
Given data
= 0.9 atm
= 50 ml
= 298 K
At STP
= 1 atm
= 273 K
From ideal gas equation
= 41.22 ml
Therefore the volume of sample at STP is = 41.22 ml
