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Analysis of a compound containing lead and chlorine reveals that the compound is 59.37% lead. The molar mass of the compound is 349.0 g/n. What is the empirical formula and the molecular formula of this compound?

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The empirical formula of the compound containing lead and chlorine is
PbCl_4, and the molecular formula is also .
PbCl_4

To determine the empirical formula of the compound, we need to find the ratio of the elements present in the compound.

First, let's assume we have 100 grams of the compound. Since the compound is 59.37% lead, we have 59.37 grams of lead. The remaining mass is due to chlorine.

To find the number of moles of each element, we divide the mass of each element by its molar mass.

The molar mass of lead is 207.2 g/mol, so the number of moles of lead is:

59.37 g / 207.2 g/mol = 0.286 mol

The molar mass of chlorine is 35.45 g/mol, so the number of moles of chlorine is:

(100 g - 59.37 g) / 35.45 g/mol = 1.148 mol

Next, we need to find the simplest whole number ratio between the two elements. We can do this by dividing the number of moles of each element by the smallest number of moles.

Dividing both values by 0.286, we get:

0.286 mol / 0.286 mol = 1

1.148 mol / 0.286 mol = 4

This means that the empirical formula of the compound is
PbCl_4, which represents one lead atom and four chlorine atoms.

To find the molecular formula, we need to know the molar mass of the compound. Given that the molar mass is 349.0 g/mol, we can calculate the empirical formula mass of
PbCl_4 as follows:

(1 atom of lead * 207.2 g/mol) + (4 atoms of chlorine * 35.45 g/mol) = 207.2 g/mol + 141.8 g/mol = 349.0 g/mol

Since the empirical formula mass matches the molar mass of the compound, the empirical formula,
PbCl_4, is also the molecular formula of the compound.

In conclusion, the empirical formula of the compound containing lead and chlorine is
PbCl_4, and the molecular formula is also
PbCl_4

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