REDOX REACTIONS

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

• Oxidized
• Reduced

Tags

NGSS.HS-PS1-2

If in a reaction, copper is reduced; its number of electrons has:

• Increased
• Decreased
• Remained Constant
• Varies Randomly

Tags

NGSS.HS-PS1-2

What is oxidation number of Cr in Cr₂O_7^2-?

• -2
• +2
• +6
• +12

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-1

What is oxidation number of H in CaH₂?

• +1
• -1
• 0
• +2

Tags

NGSS.HS-PS1-1

An increase in oxidation number.

• more acidic

• reduction

• less basic

• oxidation

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-1

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

NGSS.HS-PS1-1

The sum of the oxidation numbers in SCN^- is equivalent to

• 0

• -1

• +1

• +3

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⁺

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-1

What reaction occurs at the anode?

• Ag⁺ + e^- →Ag
• Ag → Ag⁺ + e^-
• Ni²⁺ + 2e^- → Ni
• Ni → Ni²⁺ + 2e^-

Tags

NGSS.HS-PS1-2

Which energy conversion shown below takes place in a voltaic cell?

• Electrical to chemical

• Mechanical to chemical

• Mechanical to electrical

• Chemical to electrical

Tags

NGSS.HS-PS3-3