Answer:
Divide the given mass by its molar mass to get moles, then multiply times 6.022×1023 molecules 1 mol .
Converting between molecules and moles is done by either multiplying by or dividing by Avogadro's number:
1.To go from moles to molecules, multiply the number of moles by 6.02 x 1023.
2.To go from molecules to moles, divide the numbers of molecules by 6.02 x 1023.
We know that the number of moles is equal to the weight of the substance divided by its molar mass. Therefore, the number of moles in 19.82g of Mg is 0.81 mol.
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:
Explanation:
Elements that have most similar properties were placed in the same group on the periodic table and this is done based on the number of valence electron each of the element posses which allow them reach in a similar manner as a member of the same family. A group of element is placed on a a vertical column of the periodic table.
For all element with one valence electron they are labelled with 1A on the group, and are usually the first column followed by 2A until group 8.
1A element are known to be very reactive and form compounds with similar properties with other elements.
