Redox Reactions & Oxidation Numbers

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

• Reduced
• Synthesized
• Oxidized
• None of the above

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What is the oxidation number of Fe in FeO?

• +1
• -1
• +2
• -2

Tags

NGSS.HS-PS1-2

What is oxidation number of P in K₃PO₄?

• +1
• +5
• -2
• 0

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What is oxidation number of O₂ ?

• 0
• -2
• +1
• +2

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

     In the reaction Zn + H₂O --> ZnO₂ + H₂
 which element, if any, is oxidized? 

• Zinc
• Hydrogen
• Oxygen
• None

Tags

NGSS.HS-PS1-2

What happens to Cr³⁺ ion when it is converted to CrO₄^2–

• Oxidation number decreases and it undergo reduction
• Oxidation number decreases and it undergo oxidation
• Oxidation number increases and it undergo reduction
• Oxidation number increases and it undergo oxidation

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What happens to iodine when iodate, IO₃^–, converted to iodine, I₂?

• Undergo reduction and oxidation number changes from –1 to 0
• Undergo oxidation and oxidation number changes from –1 to 0
• Undergo reduction and oxidation number change from +5 to 0
• Undergo oxidation and oxidation number change from +5 to 0

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-7

Which substance is reduced in the following reaction? 
NaOH + Li --> LiOH + Na

• Li
• Na
• O
• H

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

How many electrons are transferred in the reaction below?
4Fe + 3O₂ --> 2Fe₂O₃

• 12 electrons
• 6 electrons
• 4 electrons
• 3 electrons

Tags

NGSS.HS-PS1-7

How many electrons are transferred in the reaction below?
3 Mg + 2 AlCl₃ --> 3 MgCl₂ + 2 Al

• 2 electrons
• 3 electrons
• 6 electrons
• 10 electrons

Tags

NGSS.HS-PS1-2