Understanding Chemical Formulas

What is the primary function of a CHN analyzer?

• To determine the molecular formula of a compound

• To analyze the elemental composition of a sample

• To calculate the molar mass of a compound

• To find the empirical formula of a compound

Which formula shows the relative numbers of atoms in a compound?

• Molecular formula

• Empirical formula

• Structural formula

• Chemical formula

In the example of ethylene, what is the first step in calculating the empirical formula?

• Determining the molecular formula

• Calculating the molar mass

• Converting masses to moles

• Finding the greatest common factor

What is the purpose of creating a pseudo formula?

• To find the molecular formula

• To simplify the calculation of the empirical formula

• To analyze the elemental composition

• To determine the molar mass

How do you find the greatest common factor in the empirical formula calculation?

• By calculating the molar mass

• By trial and error starting with the smallest value

• By using the periodic table

• By dividing by the largest value

What additional information is needed to calculate the molecular formula from the empirical formula?

• The density of the compound

• The structural formula

• The molar mass of the compound

• The percentage composition

In the example of ethylene, what is the molecular formula if the empirical formula is CH2?

• C5H10

• C4H8

• C3H6

• C2H4

What is the molecular formula of cyclohexane if its empirical formula is CH2?

• C4H8

• C6H12

• C5H10

• C3H6

In the example of adamantane, what is the first step in finding the molecular formula?

• Calculating the molar mass of the empirical formula

• Finding the greatest common factor

• Analyzing the elemental composition

• Determining the percentage composition

What is the molecular formula of adamantane if its empirical formula is C5H8 and n is 2?

• C5H8

• C20H32

• C10H16

• C15H24