2. The following equation represents a commonly used method for producihg oxyeen

ID: 1037306 • Letter: 2

Question

2. The following equation represents a commonly used method for producihg oxyeen.- it by the trial-and-error method. 3. When 6.50 g of a red mercury oxide (X) were heated, the compound decomposed into mercury and oxygen. Compound X Hg o Using the data below, calculate the ratio of mercury and oxygen atoms in the compound (this is called its empirical formula) and balance the equation. Number of Moles Whole Number Molar Ratio Ratio of Atoms Molar Ratio Hg O2 Calculations: Mass 6.04 g_ 0.47 g a. The formula of compound X is: b. The balanced equation for its reaction on heating is: The name of compound X is: c.

Explanation / Answer

KClO3 undergoes decomposition to form KCl and O2. Given reaction has three atoms of oxygen on reactant side and two atoms of oxygen on product side. Thus, multiplying KClO3 by two and O2 by three should balance number of oxygen atoms on both sides. Balance KCl by multiplying it with 2.

Therefore, balanced equation is as follows:

2 KClO3 -------------------> 2 KCl + 3 O2

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Molar mass of Hg is 200.6 g/mol and that of O2 is 32.0 g/mol.

Calculate number of moles of Hg in 6.04 g as follows:

Moles of Hg = Mass / Molar mass

Moles of Hg = (6.04 g) / (200.6 g/mol)

Moles of Hg = 0.03011

Similarly calculate number of moles of O2 as follows:

Moles of O2 = Mass / Molar mass

Moles of O2 = (0.47 g) / (32 g/mol)

Moles of O2 = 0.01469

Therefore, number of moles of Hg is 0.03011moles and that of O2 is 0.01469moles.

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Calculate molar ratio by dividing number of moles with smallest number of moles as follows:

Molar ratio of Hg = Number of moles of Hg / 0.01469

Molar ratio of Hg = (0.03011) / (0.01469)

Molar ratio of Hg = 2.0496

Similarly calculate molar ratio of O2 as follows:

Molar ratio of O2 = Number of moles of O2 / 0.01469

Molar ratio of O2 = (0.01469) / (0.01469)

Molar ratio of O2 = 1.0000

Therefore molar ratio of Hg is 2.0496 and that of O2 is 1.0000.

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Substitute values in given table as follows:

Mass

Number of Moles

Molar Ratio

Whole Number Molar Ratio

Ratio of Atoms

6.04 g

0.03011

2.0496

0.47 g

0.01469

1.0000

Therefore, Formula of compound X is Hg2O2.

The balanced equation for the reaction on heating is given as follows:

Hg2O2 ----------------> 2Hg + O2

The name of compound Hg2O2 is Mercury (II) oxide. It is also called as mercuric oxide.