Among the following which is known as vitamin B12?

Options:

• Cyanocobalamin
• Retinol
• Riboflavin
• Pyridoxine

Answer: Cyanocobalamin

Cyanocobalamin:

As stated above cyanocobalamin is known as vitamin B₁₂. Actually cyanocobalamin is needed for the normal production of red blood cells. It is also required for the nerve cells. Remember that the deficiency of cyanocobalamin results in a disease known as pernicious anaemia. It is important to note that vitamin B & C are water soluble vitamins.

Retinol:

Retinol is known as vitamin A. This is a fat soluble vitamin. Do you know the deficiency disease of vitamin A? Remember that the deficency of vitamin A results in a disease known as xerophthalmia & night blindness.

Riboflavin:

Vitamin B₂ is known as riboflavin. It is interesting to note that this vitamin is seen in green vegetables, milk & liver. The deficiency of riboflavin results in inflammation of the tongue.

Pyridoxine:

Remember that the another name for pyridoxine is vitamin B₆. This vitamin is seen in cereal grains & milk. It is important to note that the deficiency of pyridoxine results in retarded growth & dermatitis.

Clemmensen reduction of benzaldehyde yields.......

Answer: Toluene

Do you know what is meant by clemmensen reduction? It is important to note that clemmensen reduction involves the reduction of aldehydes & ketones to hydrocarbons by using amalgamated Zn & concentrated HCl. This is represented by the following equation:
CH₃COCH₃---->CH₃CH₂CH₃

Among the following glassess, which type is used for making superior type laboratory apparatus?

Options:

• Pyrex glass
• Hard glass
• Soda lime glass
• Flint glass

Answer: Pyrex glass

Pyrex glass:

It is interesting to note the properties & composition of pyrex glass. The most important property of pyrex glass is that it has low coefficient of expansion. Do you know anything about the composition of pyrex glass. The composition of pyrex glass includes

• Silica 80%
• Al₂O₃ 3%
• B₂O₃ 12%
• CaO 0.5%

Hard glass:

Hard glass is also known as potash glass. Remember that hard glass has a higher melting point. Also note that if we use K₂CO₃ instead of Na₂CO₃ in the manufacturing process the product obtained is known as hard glass.

Flint glass:

Flint glass is used in making prisms because of its high refractive index.

Orthosilicates & Disilicates

Orthosilicates & disilicates are the different types of silicates. Before going into the details we should know how to represent the simplest silicate anion. Remember that the simplest silicate anion is represented as SiO₄^4-.
Orthosilicates:
It is important to note that silicates that contain the simplest silicate anion are known as orthosilicates. There are different examples for orthosilicates.
Examples for orthosilicates:
Zircon Zr[SiO₄]
Phenacite Be₂[SiO₄]
Disilicates:
Disilicates are also known in another name. Do you know which is it? Remember that disilicates are also known as pyrosilicates. Also note that disilicates contain Si₂O₇^6- units. An example for disilicate is Sc₂(Si₂O₇)

Borazine can act as a reducing agent.why?

Borazine can act as a reducing agent because it is moisture sensitive & can be hydrolysed to hydrogen & boric acid which is represented by the equation.
B₃N₃H₆ +9H₂O---> 3H₂ + 3H₃BO₃ + 3NH₃
.
Also see Borazine.

Borazine

First remember that borazine is also known in another names. Do you know which are they? Remember that borazine is also known as Borazole & Inorganic benzene. Borazine is represented by the formula B₃N₃H₆. Borazine is considered as an example for heteroatomic polymer as well as a cyclic polymer of aminoborane.
Why borazine is known as inorganic benzene?
This is an important question which chemistry students should be able to answer. We all know about physical properties & chemical properties. Remember that borazine has similar physical properties with benzene. Also note that they are aromatic as well as isoelectronic. So it is important to note that borazine is also known as inorganic benzene.
why borazine acts as a reducing agent?

Boranes

As the name indicates, boranes are hydrides of boron. They are colourless compounds with a special property that it is diamagnetic. It is important to note that there are 3 classess of boranes. Do you know which are they?
Classess of boranes:

1. Nido-boranes
2. Arachno-boranes
3. Conjuncto-boranes

The above mentioned borane classess are represented by a general formula.

General formula of borane classess:

1. Nido-boranes: B_nH_n+4
2. Arachno-boranes :B_nH_n+6
3. Conjuncto-boranes: B_nH_m

Benzoin condensation

Chemistry students should always be familiar with the reactions & reagents involved in it. My question is benzaldehyde undergoes benzoin condensation in the presence of .........

Answer:
Potassium cyanide

Reaction of glycerol & bismuth nitrate

Do you know what is the product formed when glycerol undergoes oxidation with bismuth nitrate? Remember that the product formed is mes oxalic acid.

Hardening of cement

Do you know the process involved in the hardening of cement? It is interesting to note that this is mainly due to hydrolysis & hydration.

Important question

• Why CuSO₄ is not stored in aluminium bottles?

Answer:

This is because Cu gets reduced.

What is the shape of XeF4 molecule?

• Square planar

What is the product formed when phenol reacts with phthalic anhydride in presence of concentrated sulphuric acid?

• Phenolphthalein

Example of non reducing sugar

Cane sugar

Example of lyophilic solution

Starch dispersed in hot water

Interesting question

Experiments are part of a science student. This is an interesting question. Among the 2 options given below, can you name the flame which has maximum temperature?

1. Bunsen burner
2. Oxy-acetylene

Answer is Oxy-acetylene.

Polytetrafluoroethylene is known as

Teflon

Name the product formed when phenol is heated with KOH & chloroform

• Salicylaldehyde

What is Lucas reagent?

• Lucas reagent is HCl & ZnCl₂

Which is the common variety of coal?

Coke

What is freon?

Freon is CF₂Cl₂

Do you know why handling of acetylene is dangerous?

• This is because acetylene is an explosive.