Which of the following compounds has the highest boiling point?
Correct Answer: B.Octane.
The boiling point of hydrocarbons increases as the number of carbons increases. Therefore, Heptane has a higher boiling point than hexane, which has a higher boiling point than pentane. This is because the intermolecular forces between molecules keep the hydrocarbons in solution, requiring more heat to overcome these forces and become a gas. In the case of branched molecules, the hydrocarbons are not able to “stack” as easily as straight-chain hydrocarbons. This reduces intermolecular interactions and, subsequently, the boiling point. Even though octane, 2,2-dimethylhexane, and 2-methylheptane have eight carbons, octane has the highest boiling point.
The Medical College Admissions Test (MCAT) is a test administered by the Association of American Medical Colleges (AAMC). The test is designed to test your knowledge in three specific sections; physical sciences such as physics and general chemistry, biological sciences and organic chemistry, and verbal reasoning.
How Should I Study?
The MCAT is a rigorous exam that requires months of planning in order to achieve a great score. It is recommended that you begin your study schedule 3 months prior to your exam date. In addition to answering our practice MCAT questions each day, read this article regarding studying for the MCAT from home.
Register for the MCAT.
The first question many people ask is, “when should I take the MCAT?” The general guideline is to take the MCAT the year before you plan to enter medical school. For example, the class of 2018 should take the MCAT sometime before or during the spring/summer of 2013. Your basic science coursework should be complete by this point.