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3 years ago

Why is the mass in amu of a carbon-12 atom reported as 12.011 in the periodic table of the elements?

1 answer:

7 0

The mass of an element listed in the Periodic Table is the weighted average of all its naturally occurring isotopes.

Naturally occurring carbon is about

99 % carbon-12 (12.000 u) + 1 % carbon-13 (13.003 u).

That extra carbon-13 makes the average atomic mass greater than 12.000 u.

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Fe2(SO4)3 +__BaCl2 → __BaSO4 +_ FeCl3

Elenna [48]

Answer:

Fe2(SO4)3 + 3BaCl2 → 2FeCl3 + 3BaSO4

8 0

3 years ago

The elemental analysis of an organic solid extracted from gum arabic (a gummy substance used in adhesives, inks, and pharmaceuti

Evgesh-ka [11]

Answer:

The molar mass of the organic solid is 120.16 g/mol.

The molecular formula of an organic solid is $C_4H_8O_4$

Explanation:

Let the molecular mass of an organic solid be $C_xH_yO_z$

$\Delta T_b=K_b\times m$

$Delta T_b=K_b\times \frac{\text{Mass of solid}}{\text{Molar mass of solid}\times \text{Mass of diphenyl in Kg}}$

where,

$\Delta T_f$ =Elevation in boiling point = $=1.5^oC$

Mass of organic solid= 0.561 g

Mass of diphenyl = 24.9 g = 0.0249 kg (1 kg = 1000 g)

$K_b$ = boiling point constant = 8.00 °C/m

m = molality

Now put all the given values in this formula, we get

$1.5^oC=8.00 ^oC/m\times \frac{0.561 g}{\text{Molar mass of solid}\times 0.0249 kg}$

${\text{Molar mass of solid}}=120.16 g/mol$

$\%=\frac{\text{Number of atoms}\times \text{mass of an atom}}{\text{molas mass of compound}}\times 100$

Percentage of carbon in an organic solid = 40.0%

$40\%=\frac{x\times 12 g/mol}{120.16 g/mol}\times 100$

x = 4.0

Percentage of hydrogen in an organic solid = 6.7%

$6.7\%=\frac{y\times 1 g/mol}{120.16 g/mol}\times 100$

y = 8.0

Percentage of hydrogen in an organic solid = 6.7%

$53.3\%=\frac{x\times 12 g/mol}{120.16 g/mol}\times 100$

y = 4.0

The molecular formula of an organic solid is $C_4H_8O_4$

8 0

3 years ago

Which of the following metals (M) will form an ionic compound with nitrogen with the general formula M3N2? Hint: Think about how

Basile [38]

Answer:

See explanation

Explanation:

The question is incomplete but i will try to give you all the necessary guide that you need in order to answer the question.

When compounds are formed, atoms exchange valency. The valency of nitrogen is three while that of the metal is two. The exchange yields M3N2.

If the compound has been specifically mentioned to be a metal, then it must be a group two element. It could be any of Mg, Ca, Sr, Ba or Ra. I did not mention Be here because most of its compounds are covalent.

This will help you to answer the complete question.

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3 years ago

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Dibujo de la estructura de lewis con las siguientes iones o moléculas Pbi4 y AgNO3NO

11111nata11111 [884]

i dont have a clue i dont know h ave a lcue

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3 years ago

What best explains the type of energy present in the vibrating atoms of a substance? It is thermal energy, which is a type of ki

natima [27]

What best explains the type of energy present in the vibrating atoms of a substance?

The answer is: It is thermal energy, which is a type of kinetic energy.

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3 years ago

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