Answer:

Explanation:
Hello there!
In this case, according to the given chemical reaction, it possible for us to set up the expression for the calculation of the enthalpy change as shown below:

Thus, given the values of the enthalpies of formation on the attached file, we obtain:
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Answer:
Protective fruit
Explanation:
Angiosperm seeds grow in the middle of flower's ovaries and are covered by a defensive fruit.
Hello!
The Chemical reaction is the following:
2F₂(g) + 2 H₂O(g) → O₂(g) + 4HF(g)
If we assume that all the gases are ideal gases,
we can describe the coefficients of this reaction as Volume rather than moles, so we can apply the following equations:

So,
2 L of Water Vapor reacts with the fluorine; and
1 L of Oxygen and
4 L of Hydrogen Fluoride are produced.
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