Here we have to choose the correct statement on the effect of temperature on the motion of the molecules and atoms of a gas.
As the temperature increases the molecules and atoms move faster.
As per the kinetic theory of gas molecules and atoms the kinetic energy (K.E.) of the atom or molecules is related to temperature by the equation
K.E. = 
kT ( k = Boltzmann constant, T = temperature.
Thus as the temperature increases the K.E. increases thus the atom or molecules move faster.
With the decrease of temperature the movement of the atoms or molecules will be less and they will be near to each other.
The increment of temperature increase the K.E. thus the atoms or molecules move apart from each other.
With the decrease of temperature the movement of the atoms or molecules decreases.
<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:
Evaporation is slower, occurs only from the surface of the liquid, does not produce bubbles, and leads to cooling. Boiling is faster, can occur throughout the liquid, produces lots of bubbles, and does not result in cooling.
