Explanation

Explanation

Crystals in which lattice points are occupied by metal ions are a) Ionic crystals. 

Ionic crystals are formed by the electrostatic attraction between positively charged metal cations and negatively charged anions.

These ions are arranged in a regular lattice structure. 

Explanation

A liquid crystal is a state of matter that exhibits properties of both liquids and crystals.

It requires the molecules to have a specific structure, often long and rigid, to form ordered phases.

While soap can form structures similar to liquid crystals when mixed with water (forming micelles), pure soap is not a liquid crystal.

The other options listed, DNA, cholesteryl format, and engine oil, can all exhibit liquid crystal properties under certain conditions. 

Explanation

Methylamine and hydrogen peroxide are liquids due to Hydrogen bonding. 

Hydrogen bonding is a strong type of intermolecular force

That occurs when a hydrogen atom is bonded to a highly electronegative atom 

Like oxygen, nitrogen, or fluorine. In methylamine (CH3NH2)

The nitrogen atom has a lone pair of electrons and can form hydrogen bonds with other methylamine molecules.

Similarly, hydrogen peroxide (H2O2) has hydrogen atoms bonded to oxygen atoms, allowing for hydrogen bonding.

These strong hydrogen bonds hold the molecules together in the liquid state. 

Explanation

Graham's Law of Effusion: The rate at which a gas effuses (or diffuses through a small opening like a leak) is inversely proportional to the square root of its molar mass.

This means that lighter gases escape faster than heavier gases under the same conditions.

Explanation

Van der Waals forces increase with the size and mass of the molecule due to greater electron cloud polarizability.

Among the options, Cl₂ is largest and heaviest, so it has the strongest Van der Waals forces.

Explanation

Heat of reaction refers to the amount of heat released or absorbed during a chemical reaction.

If heat is released, the reaction is exothermic; if absorbed, it's endothermic.

Explanation

A gas behaves non-ideally at low temperature and high pressure. 

At low temperatures, molecules have less kinetic energy,

Meaning they move more slowly and are more likely to experience intermolecular forces,

They cause them to deviate from ideal behavior.

High pressure also contributes to non-ideal behavior

Because the molecules are closer together, leading to increased interactions. 

Explanation

According to Graham’s Law of Diffusion, gases with lower molar mass diffuse faster.

Molar masses:

- H₂ = 2 g/mol (lowest)

- He = 4 g/mol  

- N₂ = 28 g/mol  

- CO₂ = 44 g/mol  

Since H₂ has the smallest molar mass, it will diffuse the fastest and thus escape in the least time. 

Explanation

The velocity of an electron is maximum in 1st shell

because according to Bohr's model

So we have velocity of electron = 2.188 ×10^6 m/s.

By calculation, we gained velocity= 1.094×10^6 m/s.

So it is determined that the velocity is decreased as we move from lower to higher shell