PART II: CHEM ACCELERATE

When a neutral atom forms a cation, what happens to its size?

• Increases

• Decreases

• Remains the same

• Doubles

Which of the following has the smallest radius?

• Mg

• Al

• Na

• Mg²⁺

Why is the radius of an anion larger than its neutral atom?

• Less electron-electron repulsion

• More attraction from nucleus

• Increased electron-electron repulsion and weaker nuclear attraction

• Gain of proton

______________ are ions or atoms have the same number of electrons.

Which species has the largest radius among the following isoelectronic species?

• O²⁻

• Al³⁺

• Na⁺

• Mg²⁺

Al³⁺ is smaller than Al because:

• It loses neutrons

• It gains energy

• It has more protons

• It loses electrons, reducing electron repulsion

Which of the following ions is not isoelectronic with Ne?

• Na⁺

• Mg

• F⁻

• O²⁻

Which of the following shows the correct order of decreasing ionic radius for the isoelectronic species?

• O²⁻ > F⁻ > Ne

• Ne > Na⁺ > Mg²⁺

• Al³⁺ > Mg²⁺ > Na⁺

• F⁻ > O²⁻ > N³⁻

Which of the following explains the sudden increase in ionic radius from C⁴⁺ to N³⁻ in Period 2?

• Decrease in shielding effect

• Cation becomes anion

• Extra shell present in N³⁻

• Increase in proton number

What is the trend of ionic radius from Li⁺ to C⁴⁺ across Period 2?

• Stays the same

• First increases then decreases

• Increases

• Decreases