1st Ionization Energy

Which species will require the least energy for the removal of one electron?

• Na⁺

• Mg⁺

• Al²⁺

• C³⁺

Which statement is correct?

• Atomic radius decreases down group 17.

• First ionization energy decreases down group 1.

• Atomic radius increases across period 3 from Na to Cl.

• First ionization energy decreases across period 3 from Na to Cl.

Which trends are correct across period 3 (from Na to Cl)?

I. Atomic radius decreases

II. Melting point increases

III. First ionization energy increases

• I and II only

• I and III only

• II and III only

• I, II and II

What is the definition of the term first ionization energy?

• The energy released when one mole of electrons is removed from one mole of gaseous atoms.

• The energy required to remove one mole of electrons from one mole of gaseous atoms.

• The energy released when one mole of gaseous atoms gains one mole of electrons.

• The energy required to add one mole of electrons to one mole of gaseous atoms.

Which properties decrease down group 1?

I. Melting point

II. Atomic radius

III. First ionization energy

• I and II only

• I and III only

• II and III only

• I, II and III only

The elements argon, potassium, and calcium are consecutive in the periodic table. Which gives the correct order of increasing first ionization energies?

• Ar < Ca < K

• K < Ar < Ca

• Ca < K < Ar

• K < Ca < Ar

Which statements are correct for the halogens F to I?

I. Melting point increases

II. First ionization energy increases

III. Ionic radius increases

• I and II only

• I and III only

• II and III only

• I, II and III

Which statement is correct for all elements in the same period?

• They have the same number of electrons in the highest occupied energy level.

• They have the same chemical reactivity.

• They have the same number of occupied energy levels.

• They have the same number of neutrons.

Which equation best represents the first ionization energy of magnesium?

• Mg(s) = Mg⁺(s) + e^-

• Mg(g) = Mg²⁺(g) + 2e^-

• Mg(g) = Mg⁺(g)+ e^-

• Mg(s) = Mg⁺(g)+ e^-