Q.1
An element's oxidation numbers became more negative during a reaction. What happened to that element?
  • It was oxidized
  • It was reduced
  • It was both oxidized and reduced
  • It was neither oxidized nor reduced
Q.2
Which element was reduced in the reaction below?Na + PbCl→ Pb + NaCl
  • Na
  • Pb
  • Cl
  • No element was reduced
Q.3
Which element was oxidized in the reaction below?Na + PbCl2 → Pb + NaCl
  • Na
  • Pb
  • Cl
  • No element was reduced
Q.4
If oxidation happened, then...
  • something gained electrons
  • reduction also happened
  • flames are always involved
  • oxygen is always involved
Q.5
In a redox reaction, the species reduced
  • gains electrons and is the oxidizing agent
  • loses electrons and is the oxidizing agent
  • loses electrons and is the reducing agent
  • gains electrons and is the reducing agent
Q.6
Which statement is true:Mg → Mg+ 2e–
  • Mg gains 2 electrons
  • Mg2+ loses 2 electrons
  • Mg loses 1 electron
  • Mg loses 2 electrons
Q.7
The below reaction is an example of _________reaction.F2 → 2 F- + 2 e-
  • Oxidation
  • Reduction
  • Neutralization
  • decomposition
  • combustion
Q.8
Identify the species reduced in the following reaction.Fe(s) + 2 Ag+(aq) → Fe2+(aq) + 2 Ag(s)
  • Fe
  • Ag
  • none of these
  • None of the above
Q.9
Determine the oxidation number of the selected element in each ion/ compound. a) N in N2O4 b) Cr in CrO4c) I in IO3-
  • +8, -6, +5
  • +2, +8, +6
  • +4, +6, +5
  • -4, -6, -5
  • -4, -8, -6
Q.10
What is the oxidation number of Nitrogen in HNO3
  • -7
  • -5
  • +5
  • +7
  • +2
0 h : 0 m : 1 s