How To Find The Ionic Charge Of An Element

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Ionic compounds

When a metal element reacts with a non-metal element an ionic compound is formed. An understanding of the way the elements are bonded allows us to explain their typical backdrop.

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Forming ions

Ions are electrically charged particles formed when atoms lose or gain electrons . This loss or gain leaves a full outer shell, so the electronic structure of an ion is the same as that of a noble gas (such every bit helium, neon or argon).

Metal atoms and not-metal atoms do different things when they ionise.

Metal atoms lose the electron, or electrons, in their highest energy level and become positively charged ions .

Sodium ion with a charge of 1 plus and aluminium ion with a charge of 3 plus.

Positively charged sodium and aluminium ions

Non-metal atoms gain an electron, or electrons, to get negatively charged ions .

Oxide ion with a charge of 2 minus and chloride ion with a charge of 1 minus.

Negatively charged oxide and chloride ions

Charges on ions

There is a quick way to work out what the accuse on an ion should be:

the number of charges on an ion formed by a metal is equal to the group number of the metal
the number of charges on an ion formed by a non-metallic is equal to the group number minus eight
hydrogen forms H ⁺ ions

	Group 1	Group 2	Group 3	Group 4	Group 5	Group 6	Group 7	Group 0
Example chemical element	Na	Mg	Al	C	N	O	Cl	He
Accuse	+	2+	3+	Notation 1	three-	2-	-	Annotation 2
Symbol of ion	Na ⁺	Mg ²⁺	Al ^three+	Note i	N ^3-	O ^2-	Cl ^-	Annotation ii

Note one : Carbon and silicon in Group 4 normally grade covalent bonds by sharing electrons.

Note 2 : The elements in Group 0 do not react with other elements to form ions.

Knowing the charges on the ions allows you to work out the formula of an ionic chemical compound . For instance, any compound of an element in Grouping 2 with an chemical element in Grouping 7 will need two of the Group 7 ions (X ^- ) to balance the two positive charges on the Grouping 2 ion (M ⁱⁱ⁺ ). The formula will therefore be MX ₂ .

Oxidation and reduction

When something loses electrons we say that information technology has been oxidised . When something gains electrons, we say it has been reduced . This is piece of cake to recall, using the mnemonic OIL RIG : O xidation I s L oss of electrons, R eduction I southward One thousand ain of electrons.