Hydrogen Bond

hydrogen bond is a type of attractive intermolecular force that exists between two partial electric charges of opposite polarity.As the name "hydrogen bond" implies, one part of the bond involves a hydrogen atom. The hydrogen must be attached to a strongly electronegative heteroatom, such as oxygen, nitrogen or fluorine, which is called the hydrogen-bond donor.

What is a RedOx reaction?

A RedOx reaction is the transfer of electrons between two chemical species. The compound that loses an electron is oxidized; the one that gains an electron is reduced. There are also specific terms that describe the specific chemical species. A compound that is oxidized is referred to as a reducing agent, while a compound that is reduced is referred to as the oxidizing agent.

How anti dandruff shampoo works

Anti dandruff shampoo works in three way.

1. Ingredient such as coal tar are antikeratostatic, inhibits keratinocyte cell division.

2. Detergent of shampoo are keratolytic which breaks the accumulation of scale.

3. Anti fungal agent such as ketoconazole inhibit the growth of yeast.

Why only female mosquitoes are bite

Female mosquitoes actively search for a blood meal as she needs the protein in the animals , humans blood to produce yolk for her fertilised eggs. The yolk provides the nutrients for her young.

Apple turn brown on being cut

Apple contains iron in the form of ferrous ions. These ferrous ions easily oxidise into ferric ions by air, which are in brown color, when the apple is cut, the ferrous ions of the surface oxidises to ferric ions hence brown.

How pain balm works

Pain balms generally contain 3 components i.e methyl salicylate,menthol and camphor. When balm applied, salicylate absorbed through the skin and acts as an analgesic, menthol dilates the blood vessels. Because of the increased blood flow one gets a cool sensation in the balm applied area. This is useful in case of headache and rheumatic pains. Camphor also acts as rubefacient and mild analgesic.

Sound when thumb and middle finger are clicked

A small amount of air is trapped and pressurised when the fixed end of the thumb and the free end of the middle finger are brought together. When this pressurised air is relased suddenly during the clicking it produces a sound.

Lemon drops create white spots on the floor

Citric acid of lime juice react with calcium silicates and calcium aluminates of cement on the floor, forms calcium citrate which gives a white color.

Testing of purity of Honey

Method 1: Aniline chloride test

To a small quantity of honey add few drops of aniline chloride with stirring. Appearance of crimson red color indicates adulteration.

Method 2: Granulation

Honey subjected to cool weather conditions, it granulated as sugar which is main constituent of honey. As these crystals subjected to hot water it attains normal liquid state shows, no adulteration.

Method 3: Solubility

Pure honey does not dissolve in water. Thus easily finds adulteration.

why does water taste sweet when had after a gooseberry

Amla (Indian gooseberry) is a natural rich source of vitamin C which gets oxidised easily. The fruit contains 28 % of tannin which prevents this oxidation. When hydrolysed, tannin gives Gallic acid, Ellagic acid and Glucose which is sweet. As the disslution of glucose is an endothermic reaction a cooling effect is produced.