Types of Redox Reaction

State one observation that occur at iron (II) sulphate solution when acidified potassium dichromate (VI) solution is added.

(a)  

What element is being Oxidized?

• N
• H
• O
• S

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-1

What element is being Reduced?

• N
• H
• O
• S

Tags

NGSS.HS-PS1-2

Oxygen always has an oxidation number of...

• -1
• 1
• 2
• -2

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-1

What element rusts?

• carbon

• manganese

• iron

• potassium

Tags

NGSS.MS-PS1-1

What is the chemical name given to Rust ?

• hydrated iron(I) oxide

• Iron (I) oxide

• iron(II) hydroxide

• hydrated iron(III) oxide

The diagram shows mechanism of rust formation.

Choose the correct statement:

• an iron atom release two electrons to form an iron(II) ion

• an iron(II) ion receives two electron from an iron atom

• an oxygen molecules receives two electrons to form hydroxide ion

• four hydroxide ions are formed when two water molecules receive four electrons

During rusting, the iron block also works as a voltaic cell.

Which of the following statements explain this

• there is water present

• metal iron is present

• iron atom loses electrons to oxygen and water

• iron block is corroded when in contact with oxygen and water

Diagram shows a voltaic cell on the iron block during rusting.

which of the following reaction occurs at cathode?

• Fe --> Fe²⁺ + 2e

• Fe²⁺ + 2e --> Fe

• O₂ + 2H₂O + 4e --> 4OH^-

• 4OH^- --> O₂ + 2H₂O + 4e

Name substance that undergoes oxidation?

• Water

• Zinc

• Copper (II) sulphate solution

• Copper (II) ion