Atoms

There are 8 times as many atoms in a tea-spoonful of water as there are tea-spoonfuls of water in the Atlantic ocean.

Green Chemistry

Green Chemistry is defined as the design of chemical products and processes that reduce or eliminate the use and generation of hazards substances. The ultimate aim of green chemistry or environment friendly chemistry is to prevent pollution at the source. 

Air pollution

Air pollution refers to the release into the atmosphere, of materials that are harmful to man, animals, plants and buildings or other objects. 

Noise Pollution

Noise pollution can be defined as an unwanted sound at a wrong place at the wrong time. Although noise pollution is not caused by chemicals it is equally harmful. 

Secondary Pollutants

These are formed by interaction among the primary pollutants. For example, two primary pollutants, namely, nitrogen oxides and hydrocarbons, from motor vehicles, react in the presece of sunlight to form two secondary pollutants, Peroxyacyl nitrate and ozone. These are more toxic than the primary pollutants. 

Pollution

Pollution may be defined as a change in the physical, chemical or biological aspects of the environment which make it harmful for humans, other living organisms and cultural assets. It may also be defined as an addition or excessive addition of undesirable materials to the physical environment, making its less fit or unfit fir life. 

What is Vinegar ?

Dilute aqueous solution (3%-7%) of ethanoic acid is called vinegar, which is used to preserve food. 

Fatty Acids

The long chain monocarboxylic aids are commonly called fatty acids because many of them are obtained by the hydrolysis of animal fats or vegetable oils. eg. Palmitic acid, stearic acid . 

Why aldehydes differ from ketones?

Aldehyde differ from ketones in many respects due to the presence of a hydrogen atom on the carbonyl group of aldehydes. 

Why lower member of ethers are highly inflammable?

Due to low boiling points, the lower members  are highly volatile and thus catch fire immediately. so lower ethers are highly inflammable. Like methane their vapours form explosive mixture with air. 

Why ether shave low boiling point than alcohols?

Ether have much lower boiling points compared to isomeric alcohols as they are not associated with hydrogen bonds. Their boiling points are comparable to the corresponding alkanes. 

Hydraulic Wash

This method is suitable for enrichment of heavy oxide ore. In this the powdered ore is placed on a sloping surface and washed in a strong current of water. The heavier metallic ore particles settle down at the bottom and the lighter impurities are washed away. 

Liquation

This method is used for refining those metals, which have low melting point such as tin, lead etc. The impure metal is placed on the sloping hearth of a furnace and gently heated. The metal melts and drain away leaving behind the infusible materials on the hearth. 

Matrix or Gangue

The unwanted impurities such as mud, stones, sand etc. which are present in the ore are called matrix of gangue. 

Metallic lustre

The property of metals due to which they shine is called metallic lustre. The bright lustre of metals is due to their ability to reflect the incident light from their face and the surface acquires a shining appearance, which is known as metallic lustre. Iron, silver, magnesium  aluminium etc. appear as white whereas gold is yellow and copper is reddish brown in appearance.

Chemical Equilibrium

When the rate of forward reaction becomes equal to the rate of backward reaction, this state is called chemical equilibrium. 

Stoichiometry

A branch of chemistry in which quantitative relationship between masses of reactants and products are established. The study of these laws led to the development of a theory concerning the nature of matter. 

Law of Multiple Proportion

When two elements A and B combine to form two or more  compounds, then different weights of B which combine with a fixed weight of A bears a simple numerical ratio to one another. 

Law of Conservation

The total mass of substances taking part in a chemical reaction remains the same throughout the change. 

Gay Lussac Law of Combining Volumes

Whenever gases combine there is a simple relationship between the volumes of the combining gases and this relationship extends to the volume of the product also, if gaseous, provided all the volumes are measured under the same conditions of temperature and pressure.