Why does fluorine have a higher ionization energy than oxygen?

Question

Why does fluorine have a higher ionization energy than oxygen??  
A. Smaller neutron number  
B. . Larger neutron number  
C. Smaller nuclear charge  
D. Larger nuclear charge

Accepted Answer

Correct Answer: (D)Larger nuclear charge. 
Rationale: Fluorine has a higher ionization energy than oxygen because it has a larger nuclear charge.Ionization energy is the amount of energy required to remove the most loosely bound (outermost) electron from a gaseous atom. As you move across a period on the periodic table from left to right, ionization energy generally increases. This trend occurs because the number of protons in the nucleus increases, leading to a stronger attractive force between the positively charged nucleus and the negatively charged electrons. Fluorine and oxygen are both small atoms in the same period, but fluorine has one additional proton, which significantly affects how tightly its electrons are held.A. Smaller neutron numberThe number of neutrons in an atom mainly affects the atom’s mass and nuclear stability, not how strongly electrons are attracted to the nucleus. Changes in neutron number do not significantly alter the electrostatic force between the nucleus and the electrons, so neutron number has little direct impact on ionization energy.B. Larger neutron numberThis option is also incorrect. While increasing the number of neutrons increases atomic mass, it does not increase the positive charge of the nucleus. Since ionization energy depends on the attraction between protons and electrons, neutron number is not a determining factor in explaining why fluorine has a higher ionization energy than oxygen.C. Smaller nuclear chargeA smaller nuclear charge would mean fewer protons in the nucleus, resulting in a weaker attraction between the nucleus and the electrons. Weaker attraction makes electrons easier to remove, which would lower ionization energy rather than increase it. This directly contradicts the observed trend.D. Larger nuclear chargeFluorine has nine protons in its nucleus, whereas oxygen has eight. This greater positive charge increases the electrostatic attraction between fluorine’s nucleus and its electrons. Because fluorine and oxygen have similar atomic sizes and electron shielding is minimal in the same energy level, fluorine’s higher effective nuclear charge pulls its electrons more strongly. As a result, more energy is required to remove an electron from fluorine, giving it a higher ionization energy than oxygen.ConclusionIonization energy increases across a period due to increasing nuclear charge. Fluorine’s additional proton strengthens the attraction between its nucleus and its electrons compared to oxygen, making its electrons harder to remove. This stronger nuclear pull explains why fluorine has a higher ionization energy.

Why does fluorine have a higher ionization energy than oxygen?

A
Smaller neutron number

B
. Larger neutron number

C
Smaller nuclear charge

D
Larger nuclear charge

Fluorine has a higher ionization energy than oxygen because it has a larger nuclear charge.

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Why does fluorine have a higher ionization energy than oxygen?

A Smaller neutron number B . Larger neutron number C Smaller nuclear charge D Larger nuclear charge

Fluorine has a higher ionization energy than oxygen because it has a larger nuclear charge.

Topic Flashcards

Mini Quiz

Related Questions

A
Smaller neutron number

B
. Larger neutron number

C
Smaller nuclear charge

D
Larger nuclear charge