Question

gasoline and motor oil are chemically similar. they are both mixtures of nonpolar hydrocarbons containing carbon and hydrogen atoms. however, motor oil is much more viscous than gasoline. which substance probably has the higher average molar mass?

Explanation:

Step1: Understand molar - mass and viscosity relationship

Higher molar - mass substances generally have stronger intermolecular forces.

Step2: Relate intermolecular forces to viscosity

Stronger intermolecular forces lead to higher viscosity.

Step3: Compare gasoline and motor - oil

Since motor oil is more viscous than gasoline, it has stronger intermolecular forces. So, motor oil has a higher average molar mass.

Answer:

Motor oil