Ions have what type of charge

In macroscopic samples of sodium chloride, there are billions and billions of sodium and chloride ions, although there is always the same number of cations and anions. Write the formula of the resulting ion and its electron configuration. The electron configuration of Al atom is 1 s 2 2 s 2 2 p 6 3 s 2 3 p 1. The second shell has octet 2 s 2 2 p 6 while the valence shell has 3 electrons 3 s 2 3 p 1.

Mg can achieve octet by losing the 3 valence electrons. The electron configuration of O atom is 1 s 2 2 s 2 2 p 4. The second shell has six electrons 2 s 2 2 p 4 and needs two electrons to achieve octet. Oxygen will gain 2 electrons. In many cases, elements that belong to the same group vertical column on the periodic table form ions with the same charge because they have the same number of valence electrons.

Thus, the periodic table becomes a tool for remembering the charges on many ions. Note the convention of first writing the number and then the sign on a multiply charged ion. These diagrams have two advantages over the electron shell diagrams. First, they show only valence electrons. Second, instead of having a circle around the chemical symbol to represent the electron shell, they have up to eight dots around the symbol; each dot represents a valence electron.

These dots are arranged to the right and left and above and below the symbol, with no more than two dots on a side. For example, the representation for sodium is as follows:. For the above diagrams, it does not matter what sides the dots are placed on in Lewis diagrams as long as each side has a maximum of two dots. These diagrams are called Lewis electron dot diagrams , or simply Lewis diagrams, after Gilbert N.

Lewis, the American chemist who introduced them. Up to four dots are placed above, below, to the left, and to the right of the symbol in any order, as long as elements with four or fewer valence electrons have no more than one dot in each position. The next dots, for elements with more than four valence electrons, are again distributed one at a time, each paired with one of the first four.

In other words, place the dots singly on each side before pairing them. Please check your Internet connection and reload this page. If the problem continues, please let us know and we'll try to help. An unexpected error occurred. Previous Video 2. An element is defined by the number of protons, which does not change; however, many atoms can gain or lose one or more electrons to become a charged particle.

When an atom or molecule gains or loses electrons, it is called an ion. Electrons, being much smaller in mass than protons, do not contribute significantly to the atomic mass. When atoms or molecules lose electrons, they are called cations. Cations have a positive charge because they have more protons, which have a positive charge, than electrons, which have a negative charge. Cations are given the same name as their element, followed by the word ion. A calcium atom has 20 protons and 20 electrons.

It loses two electrons to become a calcium ion with 20 protons and 18 electrons. Because it now has two more positive charges than negative charges, it has an overall charge of positive two.

The chemical symbol for an ion is written as the chemical symbol of the atom with the charge written on the right superscript position. When atoms or molecules gain electrons, they are called anions.

Anions have a negative charge because they have more electrons than protons. Anions are named by adding the suffix '-ide' to their element name. A fluorine atom has 9 protons and 9 electrons.

Fluorine gains one electron to become a fluoride ion with 9 protons and 10 electrons. Because it now has one more negative charge than positive charges, it has an overall charge of negative one.

The one is usually omitted for ions with a positive or negative one charge. Atoms will lose or gain specific numbers of electrons when forming an ion. Many of the charges for ions formed by the main group elements can be predicted using the periodic table.

The metals, on the left side of the periodic table, will lose electrons. Group 1 alkali metals all lose one electron and have a positive one charge when they become an ion. Group 2 alkaline earth metals lose two electrons and have a positive two charge. The nonmetals, on the right side of the periodic table, will gain electrons. They are generally found in a gaseous state and do not occur in abundance on Earth.

Ions in the liquid or solid state are produced when salts interact with their solvents. They are repelled by like electric charges and are attracted to opposite charges. There are specialized types of ions. Anions have more electrons than protons and so have a net negative charge.

Cations have more protons than electrons and so have a net positive charge. Zwitterions are neutral and have both positive and negative charges at different locations throughout the molecule. Anions are generally larger than the parent molecule or atom, because the excess electrons repel each other and add to the physical size of the electron cloud.

Cations are generally smaller than their parent atom or molecule due to the smaller size of their electron clouds. A positively charged ion is called a cation. Enjoy exploring several examples of ions of both types. Positive ions are typically metals or act like metals. Many common materials contain these ions. Mercury is found in thermometers , for instance, and aluminum is a metal that is found in a surprising amount of things. It's even an ingredient in baking soda and in certain other food products!

The positive charge more protons versus electrons for a cation is shown by a number and plus sign after the formula. If there's just a plus sign, it means the charge is plus 1. Review some examples of cations , or positive ions. Just as atoms can lose electrons to become cations, some can gain electrons and become negatively charged anions.