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2 years ago

Se ard 25g de magneziu de puritate 90%. Ce volum de oxigen se consumă și câti moli dioxid de magneziu se formează

Chemistry

1 answer:

alekssr [168]2 years ago

8 0

Answer:

10.5 dm3 O2

0.94 moles de MgO

Explanation:

La pregunta dice explícitamente que el magnesio es puro en un 90%.

Por lo tanto, masa de magnesio puro = 90/100 * 25G = 22,5 g

Número de moles de Mg = 22,5g / 24g/mol = 0,94 moles de Mg

La ecuación de reacción es;

2Mg (s) + O2 (g) ------> 2MgO (s)

Si 2 moles de Mg reaccionan con 1 moles de O2

0.94 moles de Mg reacciona con 0.94 * 1/2 = 0.47 moles de O2

Si 1 mol de O2 ocupa 22,4 dm3

0.47 moles de O2 ocupan 0.47 * 22.4 / 1 = 10.5 dm3

También;

2 moles de Mg producen 2 moles de MgO

Entonces, 0.94 moles de Mg producen 0.94 moles de MgO

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In the name, iron(III) oxide, the (III) represents

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<h2>In the name, iron(III) oxide, the (III) represents: D) the electrical charge of iron</h2><h2>Explanation:</h2>

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2 years ago

Two Balloons one filled with hydrogen gas and second filled with neon gas. what gas should be used in an experiement to identify

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Answer:

Oxygen

Explanation:

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2 years ago

If fluorine gas (F₂) occupies a volume of 45.5 L at a pressure of 850

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Taking into account about the ideal gas law, the mass of fluorine gas is 63.2244 grams.

<h3>What is ideal gas law</h3>

An ideal gas is a theoretical gas that is considered to be composed of randomly moving point particles that do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.

The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:

P×V = n×R×T

where:

P is the gas pressure.
V is the volume that occupies.
T is its temperature. The universal constant of ideal gases R has the same value for all gaseous substances.
R is the ideal gas constant.
n is the number of moles of the gas.

<h3>Definition of molar mass</h3>

The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

<h3>Mass of fluorine gas</h3>

In this case, you know:

P= 850 mmHg= 1.11842 atm (being 1 mmHg= 0.00131579 atm)
V= 45.5 L
T =100 °C= 373 K (being 0°C= 273 K)
R= 0.082 $\frac{atm L}{mol K}$
n= ?

Replacing in the ideal gas law:

1.11842 atm ×45.5 L = n×0.082 $\frac{atm L}{mol K}$ × 373 K

Solving:

n= (1.11842 atm ×45.5 L)÷ (0.082 $\frac{atm L}{mol K}$ × 373 K)

<u><em>n= 1.6638 moles</em></u>

The molar mass of F₂ is 38 g/mole. Then you can apply the folowing rule of three: If by definition of molar mass 1 mole of the compound contains 38 grams, 1.6638 moles of the compound contains how much mass?

$mass= \frac{1.6638 molesx38 grams}{1 mole}$