Star InactiveStar InactiveStar InactiveStar InactiveStar Inactive
 

The enthalpy change for a reaction is the same whether it occurs in one step or a series of steps.

Latest Articles

  • What's In Your Beverage? How to Ensure Quality Control with CO2 Analytical Support

    Calibration standards, performance audits, and the FDA's never-ending safety, labeling, and inspection requirements are just the tip of the iceberg when it comes to dealing with the increasingly stringent quality control standards of the beverage industry. As these quality standards become...

  • Features of the Scanning Tunneling Microscope

    The scanning tunneling microscope (STM) invented by Heinrich Rohrer and Gerd Binnig in the 1980s still manages to do a great job today and competes with more advanced microscope types. The scanning tunneling microscope is used for studying the surface atoms that are found on various materials. The...

  • Use of diamonds

    Diamond is a crystalline modification of pure carbon formed in the deep interior of the Earth, in the upper mantle at depths of more than 80-100 kilometers, at exceptionally high pressure and temperature. It is the most precious stone, the hardest and most wear-resistant mineral, the most...

  • Chemistry of the sky

    Chemistry can teach us about the composition of celestial bodies and determine their age.

  • Diamonds Are Forever

    Diamonds are still a girl's best friend, right? We love the shiny gems. They are the most popular rocks sold today. But what exactly are they, anyway? Where do they come from? What else are they used for?



Most Popular

Oxidizing Agent

The substance that oxidizes another substance and is reduced.

Foam

Colloidal suspension of a gas in a liquid.

Atomic Number


Integral number of protons in the nucleus, defines the identity of element.
 

Precipitate

An insoluble solid formed by mixing in solution the constituent ions of a slightly soluble solution.

Nuclear Reactor

A system in which controlled nuclear fisson reactions generate heat energy on a large scale, which is subsequently converted into electrical energy.

Chemical Kinetics

The study of rates and mechanisms of chemical reactions and of the factors on which they depend.

Photochemical Smog

A brownish smog occurring in urban areas receiving large amounts of sunlight, caused by photochemical (light-induced) reactions among nitrogen oxides, hydrocarbons and other components of polluted air that produce photochemical oxidants.

 

Combustible

Classification of liquid substances that will burn on the basis of flash points. A combustible liquid means any liquid having a flash point at or above 37.8°C (100°F) but below 93.3°C (200°F), except any mixture having components with flash points of 93.3°C (200°F) or higher, the total of which makes up 99 percent or more of the total volume of the mixture.

Effective Nuclear Charge

The nuclear charge experienced by the outermost electrons of an atom, the actual nuclear charge minus the effects of shielding due to inner-shell electrons.
Example: Set of dx2-y2 and dz2 orbitals, those d orbitals within a set with lobes directed along the x-, y-, and z-axes.

How to keep flowers in a vase for long time

The best gift for a woman, as you know, is a beautiful bouquet of flowers. But the cut flowers at home quite quickly wither. But your favorite roses or tulips can keep their freshness if you use our advice. Chemistry and various chemical elements will help us in this difficult matter!