Return to MCAT® Blog Homepage

MCAT Chemistry Question — Ionization Reactions

Consider the following ionization reactions:

H(g) –>  H+(g) + e-
F(g) –> F+(g) + e-

Which of the following statements is true?
A. H(g) releases energy and absorbs an electron
B. H(g) absorbs more energy than does fluorine and emits an electron
C. F(g) absorbs more energy than does hydrogen and emits an electron
D. F(g) releases energy and emits an electron

 

 

 

Explanation

A. H(g) releases energy and absorbs an electron – Incorrect
B. H(g) absorbs more energy than does fluorine and emits an electron – Incorrect
C. F(g) absorbs more energy than does hydrogen and emits an electron – Correct
D. F(g) releases energy and emits an electron – Incorrect

Both reactions depict oxidation reactions in which the atoms are ionized and lose an electron. Thus (A) is correct as it asserts that an electron is absorbed. Ionizing an element is an endothermic process in which energy is absorbed, making (D) incorrect. Comparing choices B and C, we must determine which absorbs more energy. Since fluorine is a more electronegative element, it’s going to be harder to remove an electron. This will take more energy, making C the right answer.

 

Want more MCAT practice?

We’ve got options for every schedule and learning style!

From the best online MCAT course created by top instructors with 524+ MCAT scores to the most representative full-length practice exams and private tutoring, we can custom tailor your MCAT prep to your goals!

Not sure which option is right for you? Schedule a free MCAT consultation with an MCAT Advisor using the form below. No obligation, just expert advice.

Schedule My Free Consultation

MCAT is a registered trademark of the Association of American Medical Colleges (AAMC), which is not affiliated with Blueprint.