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1 year ago

Determine the mass of oxygen in a 7.20 g sample of Al2(SO4)3.

Chemistry

2 answers:

Mekhanik [1.2K]1 year ago

5 0

Given:

7.20 g sample of Al2(SO4)3

Required:

Mass of oxygen

Solution:

Since you are not given a chemical reaction, just base your solution to the chemical formula given.

Molar mass of Al2(SO4)3 = 342.15 g/mol

7.20 g Al2(SO4)3 (1 mol/342.15g)(3mol O/2 mol Al)(1 mol O2/1/2 mol O2)(32g O2/1mol O2) = 4.04 g O2

Anarel [89]1 year ago

3 0

7.20 g of a sample of Al2(SO4)3 contains 4.04 g of oxygen.

<h2>Further Explanation</h2><h3>A compound </h3>

A compound is a substances that contains two or more different atoms that are bonded together. When the atoms are similar the substance is known as a molecule, therefore not all molecules are compounds.

<h3>Molar mass </h3>

Molar mass is the mass of one mole of a compound or a substance. The molar mass of a compound is the mass that is equivalent to the sum of relative atomic masses of the atoms of elements making up the compound.

<h3>Mass percent composition of a compound </h3>

Mass percent composition of a compound is calculated by dividing the mass of element in one mole of the compound by the molar mass of the compound and multiplying by 100%.

In this case we are require to calculate the mass of Oxygen in 7.2 g of Al2(SO4)3

Therefore; the molar mass of Al2(SO4)3 will be; 342.15 g/mol
Al2(SO4)3 is made up of two Al atoms, three sulfur atoms, and 12 oxygen atoms.

Therefore;

1 mole of Al2(SO4)3 contains a mass of 192 g of Oxygen

Thus; A sample of 7.20 g Al2(SO4)3 will contain;

= ((7.2 g Al2(SO4)3x(192 g O))/ 342.15 g/mol Al2(SO4)3

= 4.04 g Oxygen

Keywords: Molar mass, compound

<h3>Learn more about: </h3>

Compounds: brainly.com/question/1194814
Atoms: brainly.com/question/12505687
Percentage composition by mass in compounds: brainly.com/question/9118852

Level: High school

Subject: Chemistry

Topic: Compounds and mixtures

Sub-topic: Composition of compounds

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Explanation : The number of molecules of 0.5 M of sucrose is equal to the number of molecules in 0.5 M of glucose. Both solutions contain $3.011 x 10^{23}$ molecules.

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Since each substance has the same concentration, 0.5 M, each will have the same number of molecules present per liter of solution.

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Thus, these solutions compare to each other in that they have not only the same concentration, but they will have the same number of solvated sugar molecules. But the mass of glucose dissolved will be less than the mass of sucrose.

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Answer:

The answers to your questions are given below.

Explanation:

Data obtained from the question include:

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zhannawk [14.2K]

Answer: The molecular formula will be $C_8H_8O_2$

Explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

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Step 1 : convert given masses into moles.

Moles of C = $\frac{\text{ given mass of C}}{\text{ molar mass of C}}= \frac{70.6g}{12g/mole}=5.9moles$

Moles of H = $\frac{\text{ given mass of H}}{\text{ molar mass of H}}= \frac{5.9g}{1g/mole}=5.9moles$

Moles of O = $\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{23.5g}{16g/mole}=1.5moles$

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For C = $\frac{5.9}{1.5}=4$

For H = $\frac{5.9}{1.5}=4$

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Now we have to calculate the molecular formula.

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The molecular formula will be= $2\times C_4H_4O=C_8H_8O_2$

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1 year ago

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IRISSAK [1]

Answer : The molarity of the chloride ion in the water is, 5.75 M

Explanation :

As we are given that 16.6 % chloride ion that means 16.6 grams of chloride ion present 100 grams of solution.

First we have to calculate the volume of solution.

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Now we have to calculate the molarity of chloride ion.

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

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1 year ago