OCR Chemistry A – 5.2.3(a-d) Redox Titrations

When balancing redox equations, what species should be used to balance for hydrogens?

When balancing redox equations, what species should be used to balance for oxygens?

When balancing redox equations, what species should be used to balance charge?

When balancing redox equations, in what order should these steps be taken?

• balancing hydrogens

• balancing charge

• balancing redox elements

• balancing oxygens

When balancing half-equations, electrons should be added to...

• the side with the reducing agent on it

• the side with the most positive charge

• the side with the most negative charge

• the side with the H+ on

Answer explanation

not all half equations involve H+

The colour change across the end point for an Fe²⁺/MnO₄^– titration

(where permanganate is in the burette)

is ​​ (a)   to ​ (b)  

• colourless
• pale pink
• purple
• blue-black
• clear
• yellow
• pink

To convert a redox equation into alkali conditions,

​ (a)   need to be added to ​ (b)  

• hydroxide ions
• both sides
• the side with the H+ on
• water

The ratio of

MnO₄^– : Fe²⁺

is...

The ratio of

I₂ : S₂O₃^2–

is...

Iodine/thiosulfate titrations are usually used to analyse something that is not iodine.

The thing being analysed must be an...