Questions

Vitamin A is a group of unsaturated nutritional organic compounds that includes retinol, retinal, retinoic acid, and several provitamin A carotenoids.

IUPAC Name :: (2E,4E,6E,8E)-3,7-dimethyl-9-(2,6,6-trimethylcyclohexen-1-yl)nona-2,4,6,8-tetraen-1-ol

Vitamin Name - Chemical Name

Vitamin A   -     Retinol

Vitamin B1  -    Thiamine

Vitamin B2  -    Riboflavin

Vitamin B3  -    Niacin

Vitamin B5  -    Pantothenic acid

Vitamin B6  -    Pyridoxin

Vitamin B7  -    Biotin

Vitamin B9  -    Folic acid

Vitamin B12  -   Cyanocobalamin

Vitamin C     -   Ascorbic acid

Vitamin D     -   Calciferol

Vitamin E      -   Tocoferol

Vitamin K      -   Phylloquinone and Menaquinones

Town planning, Drainage system and Use of Bronze are the features of Indus Valley Civilization. Use of Iron was not the feature of this.

A place where monks live as a secluded community is Monastery.

The number of bonds between a pair of atoms is called the bond order.

Bond orders can be calculated from Lewis structures, which are the heart of the valence-bond model. Oxygen, for example, has a bond order of two.

When there is more than one Lewis structure for a molecule, the bond order is an average of these structures. The bond order in sulfur dioxide, for example, is 1.5  the average of an S-O single bond in one Lewis structure and an S=O double bond in the other.

In molecular orbital theory, we calculate bond orders by assuming that two electrons in a bonding molecular orbital contribute one net bond and that two electrons in an antibonding molecular orbital cancel the effect of one bond. We can calculate the bond order in the O₂ molecule by noting that there are eight valence electrons in bonding molecular orbitals and four valence electrons in antibonding molecular orbitals in the electron configuration of this molecule. Thus, the bond order is two.