Chemical Formulas Quiz

What is mass percent composition?

• Mass percent composition is the percentage by volume of each element in a compound.

• Mass percent composition is the total mass of a compound.

• Mass percent composition is the ratio of the number of atoms of each element in a compound.

• Mass percent composition is the percentage by mass of each element in a compound.

How do you calculate the empirical formula of a compound?

• Subtract the mass or percentage composition of each element by its atomic mass and simplify the ratios to the smallest whole numbers.

• Divide the mass or percentage composition of each element by its atomic mass and simplify the ratios to the smallest whole numbers.

• Add the mass or percentage composition of each element and simplify the ratios to the smallest whole numbers.

• Multiply the mass or percentage composition of each element by its atomic mass and simplify the ratios to the smallest whole numbers.

What is the difference between empirical and molecular formulas?

• The empirical formula is always written in lowercase letters, while the molecular formula is always written in uppercase letters.

• The empirical formula is used for ionic compounds, while the molecular formula is used for covalent compounds.

• The empirical formula represents the simplest whole number ratio of atoms in a compound, while the molecular formula represents the actual number of atoms of each element in a compound.

• The empirical formula represents the actual number of atoms of each element in a compound, while the molecular formula represents the simplest whole number ratio of atoms in a compound.

What is the notation used for chemical formulas?

• formulaic notation

• chemical notation

• chemical symbols

• molecular notation

What are the steps involved in calculating the molecular formula of a compound?

• 1. Determine the empirical formula of the compound. 2. Calculate the molar mass of the empirical formula. 3. Determine the molar mass of the compound. 4. Divide the molar mass of the compound by the molar mass of the empirical formula to find the ratio. 5. Add the subscripts in the empirical formula to get the molecular formula.

• 1. Determine the molecular weight of the compound. 2. Calculate the molar mass of the empirical formula. 3. Determine the molar mass of the compound. 4. Add the subscripts in the empirical formula to get the molecular formula.

• The steps involved in calculating the molecular formula of a compound are: 1. Determine the empirical formula of the compound. 2. Calculate the molar mass of the empirical formula. 3. Determine the molar mass of the compound. 4. Divide the molar mass of the compound by the molar mass of the empirical formula to find the ratio. 5. Multiply the subscripts in the empirical formula by the ratio to get the molecular formula.

• 1. Determine the molecular weight of the compound. 2. Calculate the molar mass of the empirical formula. 3. Divide the molar mass of the compound by the molar mass of the empirical formula to find the ratio. 4. Multiply the subscripts in the empirical formula by the ratio to get the molecular formula.

What is the mass percent composition of a compound if it contains 25 grams of carbon and 75 grams of oxygen?

• 25% carbon, 75% oxygen

• 50% carbon, 50% oxygen.

• 75% carbon, 25% oxygen.

• 10% carbon, 90% oxygen.

A compound contains 40% carbon, 6.7% hydrogen, and 53.3% oxygen. What is its empirical formula?

• C2H4O2

• CHO2

• C3H6O3

• CH2O

A compound has an empirical formula of CH2O and a molar mass of 180 g/mol. What is its molecular formula?

• C4H8O4

• C3H6O3

• C6H12O6

• C5H10O5

What is the molecular formula of a compound if its empirical formula is C2H4O and its molar mass is 88 g/mol?

• C4H8O2

• C3H6O

• C4H10O

• C2H6O2

A compound has a molar mass of 342 g/mol and an empirical formula of C6H10O5. What is its molecular formula?

• C12H20O10

• C18H30O15

• C12H22O11

• C6H10O5