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Answer:

Explanation:
Hello there!
In this case, according to the given information, it turns out firstly necessary to write out the described chemical reaction as shown below:

Now, we set up the expression for the calculation of the standard free energy change, considering the free energy of formation of each species, specially those of H2 and F2 which are both 0 because they are pure elements:

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The mass of the water is 1.20 - 0.80 = 0.40 grams.
The % of water is (0.40 / 1.20 ) * 100 = 33 1/3%
This region has both the state with the smallest population (Wyoming) and the largest population (California).
Alaska's land area is much bigger than any other state, but it has one of the lowest populations.
The western US takes up about half of the land of the United States.
The western United States is the region comprising the westernmost states of the United States. As American settlement in the U.S. expanded westward, the meaning of the term the West changed. Before about 1800, the crest of the Appalachian Mountains was seen as the western frontier.
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