Redox

The oxidation state of selenium in NaSeO₃ is

• +5

• +3

• +7

• -5

In the reaction 2Ca(s) + O₂(g) --> 2CaO(s), calcium is __________

• reduced

• oxidized

• electrolyzed

• synthesized

In the reaction N₂(g) + 3 H₂(g) --> 2 NH₃(g), nitrogen is __________.

• reduced

• oxidized

• electrolyzed

• synthesized

Oxygen usually has an oxidation number of ___ when it is combined with other elements in a compound.

• +6

• -6

• +2

• -2

Elements not combined with other elements in a compound have an oxidation number of ____.

• Depends on their group on the periodic table

• +1

• 0

• = to the number of valence elections

Oxidation is the loss of electron, meaning, there is an increase of oxidation number

• True

• False

The species that loses electron is _____ and usually _____ agent.

• oxidized;reducing

• reduced;oxidizing

• oxidized;oxidizing

• reduced;reducing

• +3

• -5

• +5

• -3

• -2

• +2

• -6

• +6

• -1

• +7

• +1

• -7