Empirical and Molecular Formulas Quiz

A chemist is analyzing a sample of a new organic compound found in a meteorite. The analysis shows that the compound consists of 40% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. Calculate the empirical formula of this compound.

• CH2O4

• C4H6O

• C2H5O3

• C3H7O2

Tags

NGSS.HS-PS1-7

A food chemist is analyzing a new sugar substitute. If the empirical formula of the substitute is CH2O and it has a molar mass of 90 g/mol, what is its molecular formula?

• C3H6O3

• C2H4O2

• C4H8O4

• CHO2

A farmer is using ammonia (NH3) as a fertilizer for his crops. He is curious about the percent composition of nitrogen in the ammonia to better understand its nutritional value for the plants. Calculate the percent composition of nitrogen in ammonia (NH3).

• 82.31%

• 93.21%

• 45.67%

• 70.45%

A chemist is working on a vinegar-based solution and discovers its empirical formula is C2H4O2. If the solution has a molar mass of 88 g/mol, what is its molecular formula?

• C4H8O4

• C3H6O3

• C6H12O6

• C5H10O5

A nutritionist is analyzing the percent composition of a new health supplement. The supplement's composition is 40% carbon, 6.7% hydrogen, and 53.3% oxygen. What is the empirical formula of this supplement?

• CH2O4

• C3H3O2

• C2H3O3

• C3H2O3

A forensic scientist finds a residue at a crime scene and determines it contains 30% carbon, 4.5% hydrogen, and 65.5% oxygen. Help them identify the empirical formula of this unknown compound.

• C₃H₃O₃

• C₂H₂O₂

• C₁H₁O₁

• C₄H₄O₄

A chemist is analyzing a sample from a newly discovered mineral on Mars. The analysis shows that the mineral contains 25.9% potassium, 28.9% chromium, and 45.2% oxygen. What is the empirical formula of this mineral?

• KCrO3

• K2Cr2O3

• K2CrO4

• K2Cr2O7

A chemist is analyzing a fuel sample and determines its empirical formula to be C3H8. If the molar mass of the fuel is found to be 72 g/mol, what is the molecular formula of the fuel?

• C5H13

• C2H6

• C6H14

• C4H10

A chemist is analyzing a sample of sulfuric acid (H2SO4) to determine its purity. What is the percent composition of sulfur in the sample?

• 45.23%

• 32.67%

• 28.14%

• 50.00%

A nutritionist is analyzing the sugar content in a popular sports drink and finds its main sugar component has a molecular formula of C6H12O6. To simplify her report, she decides to convert this to the empirical formula. What is the empirical formula of this sugar?

• C3H6O3

• CH2O

• C2H4O2

• CH3O