Chemistry Test - 11

The complex \(\left[ Co \left( NH _{3}\right)_{5}\left( NO _{2}\right)\right]^{2+}\) and \(\left[ Co \left( NH _{3}\right)_{5}( ONO )\right]^{2+}\) are called linkage isomers due to presence of \(NO _{2}\) ligand. It is an ambidentate ligands are capable of coordinating in more than one way i.e., \(NO _{2}^{-} / ONO ^{-}\).

A bilayer is composed of two sheets of phospholipid molecules with all of the molecules of each sheet aligned in the same direction. In a water medium, the phospholipids of the two sheets align so that their water-repellent, lipid-soluble tails are turned and common of which is the bilayer.

VSEPR theory is not related to the chemical kinetics.

Valence shell electron pair repulsion (VSEPR) theory is a model used in chemistry to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms. This theory is used to predict the shape of the molecules from the electron pairs that surround the central atoms of the molecule.Collision theory and absolute reaction rate both are related tochemical kinetics

A catalyst allows a chemical reaction to occur at a faster rate or under different conditions. As a result, a catalyst affects the reaction's enthalpy change. As a result, in the presence of the reaction, the enthalpy does not vary, it remains constant, and no heat is produced or absorbed. A catalyst will only lower the required activation energy for the reactions. Since it will lower the activation energy for both the forward and reverse reactions to the same extent, the net change in enthalpy is zero. So in the presence of a catalyst, the heat evolved or absorbed during the reaction remains unchanged.

When methyl Iodide is treated with sodium in the presence of dry ether, Ethane is formed.

It iscalled Wurtz reaction.

\(\mathrm{CH}_{3}-\mathrm{I}+2 \mathrm{Na}+\mathrm{I}-\mathrm{CH}_{3} \overset{_\text{Dry ether}}{\longrightarrow} \mathrm{CH}_{3}-\mathrm{CH}_{3}+2 \mathrm{NaI}\)

O-atom is ore electronegative than C-atom, therefore O-atom bears partial negative charged, and C-atom to which it is attached bear partial positive charge.Polarization in acrolein can be described by the below-given reaction:

If the accumulation of gas on the surface of a solid occurs on account of weak Van der Waals’ forces, the adsorption is termed as physical adsorption or physisorption.

Characteristics of Physisorption are:

• It is not Specific in nature
• It is a Reversible process
• It depends on thenature of gas. More easily liquefiable gases are adsorbed readily.

Enthalpy of adsorption is low.Low temperature is favourable for adsorption.There is no necessity of activation energy and it depends on the surface area. Thus, porous surfaces are good adsorbents.

There is a general trend that half filled and completely filled orbitals are more stable than incompletely filled orbitals.

\(\mathrm{C u(II)}\) is more stable than \(\mathrm{C u(I)}\) because it has a 2+ charge and is smaller than \(\mathrm{C u(I)}\).

The electron density and effective nuclear charge is greater for \(\mathrm{C u(II)}\) and it forms stronger bonds (high hydration energy) and releases more energy and is more stable.

Therefore, \(\mathrm{C u(I I)}\) is more stable than \(\mathrm{C u(I)}\).

Due to back bonding \(\mathrm{NF}_{3}, \mathrm{BCl}_{3}\) and \(\mathrm{BB}_{3}\) exist in free form. Boron form different hydride of general formula \(\mathrm{B}_{\mathrm{n}} \mathrm{H}_{\mathrm{n}+4}\) and \(\mathrm{B}_{\mathrm{n}} \mathrm{H}_{\mathrm{n}+6}\) but \(\mathrm{BH}_{3}\) is unknown.

Methyl salicylatehas a smell of oil of wintergreen.

• Methyl salicylate (oil of wintergreen or wintergreen oil) is an organic compound with the formula \(\mathrm{C}_{6} \mathrm{H}_{4}(\mathrm{OH})\left(\mathrm{CO}_{2} \mathrm{CH}_{3}\right)\).
• It is produced by many species of plants, particularly wintergreens.
• It is also produced synthetically.
• It is used as a fragrance, in foods and beverages, and in liniments.