ACIDIC BEHAVIOR OF SOLUTION
The energy that is
essential to break one C-H bond is 414 kJ/mol. Since, there are four C-H bonds
in CH4, the energy Δ HCH4 for
breaking all the bonds is calculated as Δ HCH4 = 4 x bond energy of C-H bond. By
multiplying the 4 with the 414 kJ/mol you can get the answer of 1656 kJ/mol CH4
molecules.
Answer:
<u>5 moles S x (36.02 g S/mole S) = 180.1 grams of S</u>
Explanation:
The periodic table has mass units for every element that can be correlated with the number of atoms of that element. The relationship is known as Avogadro's Number. This number, 6.02x
, is nicknamed the mole, which scientists found to be a lot more catchy, and easier to write than 6.02x
. <u>The mole is correlated to the atomic mass of that element.</u> The atomic mass of sulfur, S, is 36.02 AMU, atomic mass units. <u>But it can also be read as 36.02 grams/mole.</u>
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<u>This means that 36.02 grams of S contains 1 mole (6.02x</u>
<u>) of S atoms</u>.
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This relationship holds for all the elements. Zinc, Zn, has an atomic mass of 65.38 AMU, so it has a "molar mass" of 65.38 grams/mole. ^5.38 grams of Zn contains 1 mole of Zn atoms.
And so on.
5.0 moles of Sulfur would therefore contain:
(5.0 moles S)*(36.02 grams/mole S) = <u>180.1 grams of S</u>
Note how the units cancel to leaves just grams. The units are extremely helpful in mole calculations to insure the correct mathematical operation is done. To find the number of moles in 70 g of S, for example, we would write:
(70g S)/(36.02 grams S/mole S) = 1.94 moles of S. [<u>Note how the units cancel to leave just moles</u>]
There are 4 things that are evidence of a chemical change.
1)Change in color
2)Change in shape (gas being let out)
3)Change in temperature
4)Change in smell
Burning wood is a chemical change because it has a change in color, and shape.
Answer:
Iron is oxidized while chlorine is reduced.
Explanation:
The oxidation reduction reactions are called redox reaction. These reactions are take place by gaining or losing the electrons and oxidation state of elements are changed.
Oxidation:
Oxidation involve the removal of electrons and oxidation state of atom of an element is increased.
Reduction:
Reduction involve the gain of electron and oxidation number is decreased.
Consider the following reaction:
2FeCl₂ + Cl₂ → 2FeCl₃
in this reaction the oxidation state of iron is increased from +2 to +3. That's why iron get oxidized and it is reducing agent because it reduced the chlorine. The chlorine is reduced from -2 to -3 and it is oxidizing agent because it oxidized the iron.
2Fe⁺²Cl₂⁻²
2Fe⁺³Cl₃⁻³
The iron atom gives it three electrons to three atoms of chlorine and gain positive charge while chlorine atom accept the electron and form anion.