Empirical & Molecular Formulas

Question 1

Working backwards

Answer 1

Using Percent compositions of a compound, you can find its chemical formula using molecular and empirical formulas

Question 2

Issues with percent composition

Answer 2

• More than one compound can have the same percent composition/ratio
• CH2O and C2H4O2
• We can not determine a chemical formula just through ratios

Question 3

Empirical Formula

Answer 3

• Shows the simplest (whole number) ratios of elements in a compound
• Mole give the ratio for a compound
• Does not tell you the exact chemical formula, just the ratio

Question 4

Molecular Formula

Answer 4

• It is the exact # of each atoms in a compound
• Not reduced
• Determines the chemical formula of an unknown compound
• Ionic compounds do not have molecular formulas (no molecules) so they get their chemical formula from empirical formula
• Subscripts can be reduced, allowing for it to simplified