Question

Define: Diastereoisomers. Give cis and trans isomers of [Co(NH3)4Cl2]+.
What is reference electrode?
Give reason : Bleaching action of ozone is also called dry bleach. 

Answer 1

Diastereoisomers: Diastereoisomers are stereoisomers that are not mirror images of each other and differ in the arrangement of ligands in space.

Explanation:In coordination compounds, diastereoisomerism occurs due to different spatial arrangements of ligands around the central metal ion without being mirror images.

For the complex [Co(NH₃)₄Cl₂]⁺:

- When the two Cl ligands are adjacent, the complex is **cis-isomer**. - When the two Cl ligands are opposite to each other, it is the **trans-isomer**.

Structures:
Cis-isomer: Cl–Co–Cl angle = 90° 
Trans-isomer: Cl–Co–Cl angle = 180°

Both are diastereoisomers of each other.

A reference electrode is an electrode that has a known and constant electrode potential and is used to measure the potential of other electrodes.
Explanation: Reference electrodes provide a stable potential against which the potential of the working electrode can be compared.

Examples include:

• Standard Hydrogen Electrode (SHE): E° = 0.00 V
• Calomel Electrode (Hg/Hg₂Cl₂ in KCl)
• Silver–Silver Chloride Electrode (Ag/AgCl)

 

The bleaching action of ozone is called dry bleach because it does not require the presence of moisture or water for bleaching.
Explanation: Ozone bleaches substances by oxidation, not by reduction or hydrolysis. It oxidizes colored substances to colorless products in the absence of water.

In contrast, bleaching agents like chlorine require moisture (forming HOCl) for bleaching, hence called wet bleach.

Reaction: \[ O_3 \rightarrow O_2 + [O] \] The nascent oxygen oxidizes the colored material to a colorless form.