Chemistry

Ion

An ion is an atom or a molecule in which the total number of electrons is not equal to the total number of protons, giving the atom or molecule a net positive or negative electrical charge.

Anion

Anions are atoms or radicals which are a group of atoms, that have gained electrons. Since they now have more electrons than protons, anions have a negative charge. For example Chloride ions Cl- , Bromide Br- , Iodide I-. These are monovalent anions as it has a combining capacity with only one ion of Hydrogen.

Ionic bond

Ionic bonding is a type of chemical bond that involves the electrostatic attraction between oppositely charged ions, and is the primary interaction occuring in ionic compounds. The ions are atoms that have lost one or more electrons (known as cations) and atoms that have gained one or more electrons (known as anions).

Lewis dot structure

Lewis structures (also known as Lewis dot diagrams, electron dot diagrams, Lewis dot formulas, Lewis dot structures, and electron dot structures) are diagrams that show the bonding between atoms of a molecule and the lone pairs of electrons that may exist in the molecule.

Molecular

Molecular compounds are usually between two or more nonmetals. The nonmetals simply share their valence electrons for a full octet. When the difference in electronegativity of two atoms is greater than 1.7, the bond is ionic. When it is less than 1.7 but greater than 0.4, the bond is polar covalent

Nonpolar bond

Nonpolar covalent bonds are a type of chemical bond where two atoms share a pair of electrons with each other. Polar covalent bonding is a type of chemical bond where a pair of electrons is unequally shared between two atoms.

Element

A chemical element or element is a chemical substance consisting of atoms having the same number of protons in their atomic nuclei.

Chemical formula

A chemical formula is a way of expressing information about the proportions of atoms that constitute a particular chemical compound, using a single line of chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and plus (+) and minus (−) signs.

Compound

A compound is a molecule made of atoms from different elements. All compounds are molecules, but not all molecules are compounds. Hydrogen gas (H2) is a molecule, but not a compound because it is made of only one element.

Covalent bond

A covalent bond is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs and the stable balance of attractive and repulsive forces between atoms when they share electrons is known as covalent bonding.

Lewis dot symbol

A way of representing atoms or molecules by showing electrons as dots surrounding the element symbol. One bond is represented as two electrons.Jul 26, 2004

Electronegativity

Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons. The Pauling scale is the most commonly used. Fluorine (the most electronegative element) is assigned a value of 4.0, and values range down to caesium and francium which are the least electronegative at 0.7.

Subscript

In chemical formulas the number of atoms in a molecule is written as a subscript, so we write H2O for water which has two atoms of hydrogen for each one of oxygen.

Valence Electron

In chemistry, a valence electron is an electron that is associated with an atom, and that can participate in the formation of a chemical bond; in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair.

Ionic compound

In chemistry, an ionic compound is a chemical compound in which ions are held together in a structure by electrostatic forces termed ionic bonds. The compound is neutral overall, but contains positively charged ions called cations and negatively charged ions are called anions.

Polar covalent bond

Polar covalent bonds are a particular type of covalent bond. In a polar covalent bond, the electrons shared by the atoms spend a greater amount of time, on the average, closer to the Oxygen nucleus than the Hydrogen nucleus.

Metallic bonds

The metallic bond is the force of attraction between these free electrons and metal ions. Metallic bonds are strong, so metals can maintain a regular structure and usually have high melting and boiling points. Atomic structure of a metal.

Octet rule

The octet rule is a chemical rule of thumb that reflects observation that atoms of main-group elements tend to combine in such a way that each atom has eight electrons in its valence shell, giving it the same electronic configuration as a noble gas.

What are three properties of ionic compounds

This means that ionic compounds have high melting points and boiling points. Solid ionic compounds do not conduct electricity, because the ions are held firmly in place. They cannot move to conduct the electric current. But when an ionic compound melts, the charged ions are fee to move.

Cation

cation - a positively charged ion. hydrogen ion - a positively charged atom of hydrogen; that is to say, a normal hydrogen atomic nucleus. ion - a particle that is electrically charged (positive or negative); an atom or molecule or group that has lost or gained one or more electrons.