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3 years ago

Mole-Atom Conversions

Chemistry

1 answer:

iragen [17]3 years ago

7 0

Answer:

Explanation:

1) How many moles are 1.55 × 10²⁷ atoms of zinc?

Answer:

0.26 × 10⁴ mole

Explanation:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 × 10²³ molecules of water

1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen

For 1.55 × 10²⁷ atoms of zinc:

1.55 × 10²⁷ atoms × 1 mole/ 6.022 × 10²³ atoms

0.26 × 10⁴ mole

2) How many atoms are in 25.0 moles of calcium?

Answer:

150.55 × 10²³ atoms.

Explanation:

According to Avogadro number,

one mole of substance = 6.022 × 10²³ atoms

The number 6.022 × 10²³ is called Avogadro number.

For 25.0 moles of calcium:

one mole of calcium = 6.022 × 10²³ atoms

25.0 mole × 6.022 × 10²³ atoms /1 mole

150.55 × 10²³ atoms.

So 25.0 moles of calcium contain 150.55 × 10²³ atoms.

3) = How many atoms are in 0.35 moles of carbon?

Answer:

2.12× 10²³ atoms.

Explanation:

According to Avogadro number,

one mole of substance = 6.022 × 10²³ atoms

The number 6.022 × 10²³ is called Avogadro number.

For 0.35 moles of carbon:

one mole of carbon = 6.022 × 10²³ atoms

0.35 mole × 6.022 × 10²³ atoms /1 mole

2.12× 10²³ atoms.

So 0.35 moles of carbon contain 2.12× 10²³ atoms.

4 ) How many moles are 7.6 × 10²⁴ atoms of hellium?

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 × 10²³ molecules of water

1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen

For 7.6 × 10²⁴ atoms of hellium:

7.6 × 10²⁴ atoms × 1 mole/ 6.022 × 10²³ atoms

12. 6 mole

Mass - Mole conversion:

How many moles in 28.0 gram of oxygen?

Answer:

1.75 mol

Explanation:

Given data:

Mass of oxygen = 28 g

Number of moles = ?

Solution:

Formula:

Number of moles = mass/ molar mass

Molar mass of oxygen = 16 g/mol

Now we will put the values in formula:

Number of moles = 28 g / 16 g/mol

Number of moles = 1.75 mol

So 28 g of oxygen contain 1.75 moles.

3) Find the number of moles of argon in 452 g?

Answer:

11.31 mol

Explanation:

Given data:

Mass of argon = 452 g

Number of moles = ?

Solution:

Formula:

Number of moles = mass/ molar mass

Molar mass of argon= 39.95 g/mol

Now we will put the values in formula:

Number of moles = 452 g /39.95 g/mol

Number of moles = 11.31 mol

So 452 g of argon contain 11.31 moles.

2) What is the mass of 5.0 moles of iron?

Answer:

Mass = 279.25 g

Explanation:

Given data:

Mass of iron = ?

Number of moles of iron = 5.0 mol

Solution:

Formula:

Mass = number of moles × molar mass

Molar mass of iron = 55.85 g/mol

Now we will put the values in formula:

Mass = number of moles × molar mass

Mass = 5 mol × 55.85 g/mol

Mass = 279.25 g

4) Find the grams of 16.5 mole of hydrogen?

Answer:

Mass = 16.632 g

Explanation:

Given data:

Mass of hydrogen = ?

Number of moles of hydrogen = 16.5 mol

Solution:

Formula:

Mass = number of moles × molar mass

Molar mass of hydrogen = 1.008 g/mol

Now we will put the values in formula:

Mass = number of moles × molar mass

Mass = 16.5 × 1.008 g/mol

Mass = 16.632 g

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The variation of one or several of the following factors can alter the equilibrium condition in a chemical reaction:

Temperature
The pressure
The volume
The concentration of reactants or products

In the case of the reaction in the question, the change that moves the balance to the left will be the one that moves it towards the reagents, that is, that favors the production of reagents instead of products.

Decreasing the concentration of SO3 and increasing the concentration of SO2 will favor the production of SO3, which is the product of the reaction.
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The reaction of the question is an exothermic since ΔH <0, therefore in the reaction heat is produced and it can be written in the following way,

2SO2(g) + O2(g) ⇌ 2SO3(g) + heat

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Explanation:

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The chemical reaction for the same will be as follows.

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