Oxidation - Reduction Reaction

What is the oxidation number assigned to manganese in KMnO₄?

• ⁺7

• ⁺2

• ⁺4

• ⁺3

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

In which substance does sulfur have a negative oxidation number?

• S

• CaSO₄

• Na₂S

• SO₂

- What is the oxidation number of chromium in K₂Cr₂O₇

• +6

• +3

• +5

• +2

Given the electrochemical cell reaction:

 Zn_(s) + Ni²⁺ _(aq) → Zn²⁺ _(aq) + Ni_(s)

Which species is the reducing agent?

• Ni²⁺

• Zn

• Ni

• Zn²⁺

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

Tags

NGSS.HS-PS1-2

What element is an oxidizing agent?

• Na

• Ca

• K

• a. F₂

Which half-reaction correctly represents reduction?

• S^2– → S + 2e–

• Mn⁷⁺ → Mn⁴⁺ + 3e–

• Mn⁷⁺ + 3e– → Mn⁴⁺

• S^2– + 2e– → S

The oxidation number of Hydrogen in KH potassium hydride equals:

• -2

• -1

• +1

• +2

place in order the steps used to balance an equation by the oxidation number method .

Balance the following equations, assuming all reactions take place in an acidic solution. Show your work.

Cr₂O₇^-2 + I^- = Cr⁺³ + I₂