Chemical reactions

Synthesis.1

Voice over

Molecular naming conventions Every chemical element has its own name.

They are sometimes based on the first letter.

H for HydrogenO for Oxygen

Sometimes the letters have nothing to do with the element.

Au Gold

Voice-over text

A molecule is when different elements are bonded together.

Concept mapA synthesis reaction or direct combination reaction is one of the most common types of chemical reactions. In a synthesis reaction two or more chemical species combine to form a more complex product. Atoms have neutron and

• Valency • Electron• Proton• Atoms

Dumping ground • In the simplest view of a so-called 'covalent' bond, one or more

electrons (often a pair of electrons) are drawn into the space between the two atomic nuclei. Here the negatively charged electrons are attracted to the positive charges of both nuclei, instead of just their own. This overcomes the repulsion between the two positively charged nuclei of the two atoms, and so this overwhelming attraction holds the two nuclei in a fixed configuration of equilibrium, even though they will still vibrate at equilibrium position. In summary, covalent bonding involves sharing of electrons in which the positively charged nuclei of two or more atoms simultaneously attract the negatively charged electrons that are being shared. In a polar covalent bond, one or more electrons are unequally shared between two nuclei.

• 4

H

Hy

Hyd

Hydr

Hydro

Hydrog

Hydroge

Hydrogen

Hydrogen

Hydrogen h

Hydrogen hy

Hydrogen hyd

Hydrogen hydr

Hydrogen hydro

Hydrogen hydrogeno

Hydrogen hydrogenox

Hydrogen hydrogenoxy

Hydrogen hydrogenoxyg

Hydrogen hydrogenoxyge

Hydrogen hydrogenoxygen

water

• In the end this is water also known as H2o . H2o is 2 hydrogen’s and 1 oxygen’s.