Science

CUET 2025 Eligibility for Geology,

- *Academic Requirements*: Class 12 with 50% aggregate score, Physics, Chemistry, and Mathematics or Biology

- *University-Specific Criteria*:

    - Babasaheb Bhimrao Ambedkar University: 50% in Science (45% for SC/ST/PwD)

    - Central University of Jharkhand: 50% aggregate marks in Science (45% for SC/ST/PwD/OBC)

    - Central University of Karnataka: 50% aggregate marks (45% for SC/ST/PwD/OBC/EWS)

To apply,

1. Visit the official CUET website

2. Check university-specific eligibility criteria

3. Contact universities for clarification

Ensure you meet the requirements for a smooth application process.

Diazonium salts are formed by treating primary aromatic amines (such as aniline) with nitrous acid (generated in situ from NaNO? and HCl) at low temperatures (0–5°C). A common example is benzene diazonium chloride (C? H? N? Cl? ). Diazonium salts contain the functional group –N? X? , where X? is typically a halide like Cl? or Br?

These salts are important because they are highly reactive intermediates used in various chemical processes, Check below;

• Azo dye synthesis (via coupling reactions)

• Replacement reactions to introduce functional groups like –OH, –CN, –X (halides)

• Various organic conversions in synthetic chemistry (vital role in dye, drug, and polymer industries)

Amines are prepared by replacing the hydrogen atom with alkyl or aryl groups from amonia (NH? ). Students can differntiate Aliphatic and aromatic amines differ based on the type of group attached to the nitrogen atom. 

• Aliphatic amines have one or more alkyl groups (like methyl or ethyl) bonded to the nitrogen, such as ethylamine (CH? NH? ). 
• Aromatic amines have an aryl group (like benzene) directly bonded to nitrogen, for example, aniline (C? H? NH? ).

Aliphatic amines are generally more basic than aromatic amines because, in aromatic amines, the lone pair on nitrogen is delocalized into the aromatic ring through resonance, reducing its availability for protonation. This structural difference affects their chemical reactivity, basicity, and physical properties.

Poisson's Ratio (? ) is used when a material is subjected to axial stress. It is the ratio of lateral strain to longitudinal strain. Mathematically, it is:

Derivation of the Poisson Ratio includes when a material is stretched, its width decreases (called lateral strain) and its length increases which is called longitudinal strain.

Poisson's Ratio (? ) is a dimensionless quantity and it is normally between a range of 0 to 0.5 for most materials. It is used in engineering applications including for bridge and building design. It is used in analyzing the structural deformations. Materials like rubber which has a high Poisson's ratio when stretched, exhibit significant lateral expansion.