Answer:
I think it’s D but not sure
Explanation:
<span>These are five questions with its five answers.
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</span><span>First, we have to explain main question.
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</span><span>The statement provides the chemical equation for the reaction of Fe with water to produce iron(III) oxide and hydrogen.
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</span><span>Fe3O4 is a weird chemical formula. It belongs to the product named oxoiron.
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Next, I have to tell how you must interpret the question. The five questions are based on the complete reaction of the same number of moles as the coefficients indicated in the chemical equation.
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<span>Those coefficients are 3 for Fe, 4 for H₂O, 1 for Fe₃O₄ and 4 for H₂.
With that understood, let's work every question.
1) How many molecules of H₂ are produced?
Answer: 4 moles of molecules.
</span><span>Justification:
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<span /><span /><span>This is, the number of moles of H₂ produced is given by the coefficient indicated in the chemical equation.
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<span>2) How many oxygen atoms are required?
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<span>Answer: 4.
</span><span>This is, the atoms of oxygen are supplied in the molecules of water. Since the coeffcient of water is 4, and each molecule o fwater has 1 atom of oxygen, 4 moles of water contain 4 moles of atoms of oxygen.
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3) How many moles of Fe₃O₄ are formed?
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<span>Answer: 1.
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<span>Justification: the coefficient of for formula Fe₃O₄ is 1, indicating that the theoretical yield is 1 mol of molecules.
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<span>4) What is the mole ratio of Fe to H₂O?
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<span>Answer: 3:4
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<span>Justification:
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</span><span>The ratio is the quotient of the two coefficients: the coefficient of the Fe divided by the coefficient of the H₂O.
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5) How many hydrogen atoms are involved in this reaction?
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<span>Answer: 8 moles of hydrogen atoms.
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<span>Justification: as you can see each molecule of H₂O has 2 atoms of hydrogen, then 4 moles of molecules of H₂O have 8 moles of atoms of hydrogen. And of course the same number are in the produt: 4 moles of H₂ contain 8 moles of atomos of hydrogen
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Answer:
10
Explanation:
you need to balance the reaction. the left must be equal to the fight hànd. multiply both sides by 2
Answer:
Chemical reaction A, because the reactant is a compound
Explanation:
In a decomposition reaction, a compound is broken down into its components, so the number of products is greater than the number of reactants
Answer:
The heat needed to boil 1 gallon of water is 81,490.62 Joules.
Explanation:

Where:
Q = heat absorbed or heat lost
c = specific heat of substance
m = Mass of the substance
ΔT = change in temperature of the substance
We have :
Volume of water = V = 1 gal = 4546.09 mL
Density of water , d= 1 g/mL
mass of water = m = d × V = 1g/mL × 4546.09 mL = 4546.09 g
Specific heat of water = c = 1 Cal/g°C
ΔT = 100°C - 25°C = 75 °C
9 (boiling pint of water is 100°C)
Heat absorbed by the water to make it boil:

1 calorie = 4.184 J

The heat needed to boil 1 gallon of water is 81,490.62 Joules.