Chemistry Questions

An ionic bond is formed between two molecules when transfer of valency electrons take place between them. 

Covalent bonding occurs when pairs of electrons are shared by atoms. Atoms will covalently bond with other atoms in order to gain more stability, which is gained by forming a full electron shell. By sharing their outer most (valence) electrons, atoms can fill up their outer electron shell and gain stability.

Examples of compounds with covalent bonds ::

HCl, CO2, O2,... 

Atoms of the same element can have same atomic number and number of electrons since, the atomic number is the number of protons and the number of protons and eectrons are the same in an element.

Hence, the atoms of the same element may differ in their atomic mass since it depends on the number of neutrons it holds and such atoms are called isotopes.

In a concentrated solution there is a large amount of solute.

Isotopes are variations of an element that have the same charge as the original element, but a different mass, which is caused by either more/less neutrons in the nucleus.

When exposed to certain frequencies of radiation, such as radio waves, the subatomic particles called electrons that orbit an atom's nucleus will "jump" back and forth between energy states. Clocks based on this jumping within atoms can therefore provide an extremely precise way to count seconds.It is no surprise then that the international standard for the length of one second is based on atoms. Since 1967, the official definition of a second is 9,192,631,770 cycles of the radiation that gets an atom of the element called caesium to vibrate between two energy states.

The complexity and variety of organic molecules is due to the chemical versatility of carbon atoms.