Half Equations

Which statement is true:
Mg → Mg²⁺ + 2e^–

• Mg gains 2 electrons
• Mg_²⁺ loses 2 electrons
• Mg loses 1 electron
• Mg loses 2 electrons

Tags

NGSS.HS-PS1-2

What substance is oxidized in the following reaction?
4Fe + 3O₂ --> 2Fe₂O₃

• Iron
• Fluorine
• Oxygen

Is calcium oxidized or reduced in the following reaction? 
2CaO--> 2Ca + O₂

• Oxidized
• Reduced

Tags

NGSS.HS-PS1-2

Which of the following half reactions correctly represents a reduction half reaction?

• Fe →Fe²⁺ + 2e^-
• Pb⁴⁺ + 2e^- →Pb²⁺
• 2O^-2 →O₂ + 4e^-
• Fe + 3e^- →Fe³⁺

Which of the following is the balanced half -reaction for the oxidation of Cu to Cu^+2?

• Cu   --> Cu⁺²
• Cu + 2 e-   --> Cu⁺²
• Cu  --> Cu⁺²  + 2 e-
• Cu - 2e-  --> Cu⁺²

What is a half-reaction of this equation, Na + Cl --> NaCl ?

• Cl + e^- --> Cl^-

• Cl - e^- --> Cl^-

• Na --> Na + e^-

• Na° + Cl°--> Na⁺¹Cl^-1

Tags

NGSS.HS-PS1-2