Interpretation:
The empirical formula and molecular formula of a compound has to be given.
Concept Introduction:
Empirical Formula:
The empirical formula of a compound is the simplest whole number ratio of each type of atom in a compound. It can be the same as the compound’s molecular formula but not always. An empirical formula can be calculated from information about the mass of each element in a compound or from the percentage composition.
The steps for determining the empirical formula of a compound as follows:
- Obtain the mass of each element present in grams.
- Determine the number of moles of each atom present.
- Divide the number of moles of each element by the smallest number of moles.
- Convert the numbers to whole numbers. The set of whole numbers are the subscripts in the empirical formula.
Molecular formula:
The molecular formula is the expression of the number of atoms of each element in one molecule of a compound if the molar mass value is known the molecular formula is calculated by the empirical formula.
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FOUND.OF COLLEGE CHEMISTRY
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