oxidation numbers of transition elements

What is the oxidation number of Fe in FeO?

• +1
• -1
• +2
• -2

What is oxidation number of Mn in MnO₂ ?

• 0
• +2
• -2
• +4

What is oxidation number of Cr in
Cr₂O₇^2-?

• -2
• +2
• +6
• +12

What are oxidation numbers?

• Number of electrons in the outer most energy level
• Number of protons
• Electrons gained or lost in chemical bonding
• Number of neutrons gained or lost

What are valence electrons?

• Number of electrons in the outer most energy level
• Number of electrons gained or lost
• Number of electrons in the inner energy level
• Number of electrons 

Electron subshells are most stable

• with all orbitals full or all empty

• with orbitals exactly 3/4 full

• with orbitals exactly 3/4 empty

• with orbitals exactly 1/2 full

Predict how the valence electrons in iron metal (iron 0) should be organized.

• 
• 
• 
• 

The electron configuration of an atom is 1s²2s²2p⁶.  The number of electrons in the atom is 

• 3
• 6
• 8
• 10

Tags

NGSS.HS-PS1-1

What atom matches this electron configuration?
1s²2s²2p⁶3s²3p⁶4s²3d¹⁰

• Zinc
• Copper
• Nickel
• Germanium

Why is zinc not considered a transition metal?

• Zinc is not a transition metal because it gains two 4s electrons to give a 2+ion with full d subshell levels.

• Zinc is not a transition metal because it loses four 4s electrons to give a 4+ion with full d subshell levels.

• Zinc is not a transition metal because it loses two 4s electrons to give a 2+ion with full d subshell levels.

• Zinc is not a transition metal because it gains two 4d electrons to give a 2+ion with full d subshell levels.