Ionic CompoundTopSub Topics
1. Ionic Compound Definition2. Ionic Compound Formula3. Ionic Compound Examples4. Ionic and Molecular Compounds5. Ionic and Covalent Compounds6. Binary Ionic Compound7. Rules for Naming Ionic Compounds8. Ionic Compounds List9. Ionic Compound Properties10. Ionic Compound Characteristics11. Ionic Compound Nomenclature12. Ionic Compound PracticeSubstances resulting from the chemical combination of two or more elements in fixed proportions are called compounds. Most elements do not exist in their free native state but are in the combinations of two or more elements as chemical compounds. In ionic compounds the constituent elements exist as ions. Ions are atoms or groups of atoms that carry a charge by virtue of losing or gaining one or more electrons.
Ionic compounds result from the combination of a positive ion known as a cation and a negative ion called an anion. Atoms in a compound are held together by covalent bonds.Bonds dictate how atoms are held together in a compound or molecule,but ionic compounds are composed of ions.
Ionic Compound DefinitionBack to Top
Definition of ionic compound
An ionic compound is composed of cations and anions joined together. Such compounds are held together by electrostatic forces, and adopt structures that maximize the attraction of oppositely charged species and minimize the repulsion between charged species with the same sign.To define ionic compound in simple words"its a combination of metals with nonmetals."Ionic Compound FormulaBack to Top
Every ionic compound contains discrete ionic units with specific charges. In addition ionic compounds must always contain equal amounts of positive and negative charge. These requirements dictate the ratio of cations to anions in an ionic substance. The chemical formula of an ionic compound identifies its ionic units and the cation-to-anion ratio.
The following guidelines ensure uniformity in writing formulas for ionic compounds. The formula unit of an ionic compound shows the1. The cation is always listed before the anion.2. The formula of any polyatomic ion is written as a unit.3. Polyatomic ions are placed in parentheses with subscripts to indicate ratios different from 1:1.Ionic Compound ExamplesBack to Top
A chemical compound must have a net charge of zero. If it contains ions, the charges of the ions must add up to zero in the formula for the compound. An ionic compound exists as a group of charged atoms. The chemical formula for an ionic compound represents the positive charge of the cation equals the negative charge of the anion. Consequently the overall charge is zero, and the ionic compound is neutral.
Give two examples of an ionic compound
Example of an ionic compound is given by considering the two common ionic compounds.
1. Sodium chloride (NaCl)2. Magnesium oxide (MgO)Some example of ionic compound are listed below.S.NoIonic compoundFormula
1Sodium bromideNaBr
2Potassium sulfideK2S
3Zinc sulfateZnSO4
4Ammonium phosphate(NH4)3PO4
5Aluminum chromateAl2(CrO4)3
Ionic and Molecular CompoundsBack to Top
Compounds can be divided into two classes ionic or molecular compound. They are described in the following table. The chemical formulas of the compounds show the elements that compose them.
Ionic vs molecular compounds table is given below.
S.NoIonic compoundsMolecular compounds
1Compounds are formed by combination of reactive metals with reactive non metals.Compounds are formed by the combination of nonmetals with other non metals or with less reactive metals.
2Crystalline solids.Solids, liquids and gases.
3Hard and brittle.Solids are brittle and weak or soft and waxy.
4High melting points.Low melting points.
5High boiling points.Low boiling points.
6Good conductors of electricity when molten, poor conductors of electricity and heat when solid.Poor conductors of heat and electricity.
7Many are soluble in water.Many are insoluble in water but soluble in organic solvents.
Ionic and Covalent CompoundsBack to Top
The ionic vs covalent compounds table is given below.S.NoIonic compoundsCovalent compounds
1Crystalline solids (made of ions)Solids, liquids and gases (made of molecules)
2High melting and boiling points.Low melting and boiling points.
3Conduct electricity when melted.Poor electrical conductor in all phases.
4Many soluble in water but net is non polar liquids.many soluble in non polar liquids but not soluble in water.
Binary Ionic CompoundBack to Top
Binary Ionic Compound DefinitionA binary compounds contains only two elements. In a binary ionic compound, both of the elements are present ions. The name of the compound consists of the name of the metal from which the cation was formed, by the name of anion.
Potassium and Sulfur Ionic CompoundConsider an ionic compound formed when potassium reacts with sulfur. Potassium is a Group 1A metal, so a potassium atom loses one electron to become a K+ion. Sulfur is a Group 6A nonmetal, so a sulfur atom gains two electrons to become an S2-ion. To make the compound electrically neutral two K+ions are needed for each S2-ion. Consequently the compound has the formula K2S.Rules for Naming Ionic CompoundsBack to Top
The following rules apply for naming ionic compounds.
1. A simple cation has the same name as its parent element.2. The cation is always named first and the anion second.3. A simple cation takes its name from the name of the element. For example, Na+is called sodium in the names of compounds containing this ion.4. A simple anion is named by taking the first part of the element name and adding -ide. Thus the Cl-ion is called chloride.5. In some cases the cation can assume more than one charge, the charge is specified by a Roman numeral in parentheses.Ionic Compounds ListBack to Top
Ionic compounds are composed of cations and anions.The attraction between these oppositely charged ions is called anionic bond.The common ionic compound is given below as ionic compound table.
S.NoIonic compoundFormula
1Zinc oxideZnO
2Magnesium chlorideMgCl2
3Copper sulfideCuS
4Potassium bromideKBr
5Calcium iodideCaI2
6Aluminum oxideAl2O3
Ionic Compound PropertiesBack to Top
Properties of an Ionic Compound
The positive and negative ions formed during ionic bonding are held together by enormously strong forces of attraction between the oppositely charged ions. These ionic bonds between the charged particles result in a giant structure of ions.
Because the ions are held together tightly in these giant structures it takes a lot of energy to break all the bonds. As a result ionic compound melting point and boiling points are high.Ionic Compound CharacteristicsBack to Top
There are many important characteristics of compounds having ionic bonds.1. An ionic compound is a collection of an equal number of positive and negative ions arranged in a three-dimensional lattice.2. Ionic compounds can be dissociated into their constituent ions with little effort.3. Further they can be electrolyzed to produce elements or covalent molecules of the constituent atoms.4. Water also weakens the attraction between the ions in an ionic compound.5. This is why ionic compounds dissolve well in water.6. Moreover ionic compounds can conduct electricity.7. Most ionic compounds are made of metals.
Is Water an Ionic Compound?Water is a polar solvent and polar and ionic compounds tend to dissolve in water. So water is ionic solvent.
Is SO2an Ionic Compound?SO2is not ionic but molecular compound, no electrons are actually transferred in the formation of this compound.
Is Salt an Ionic Compound?Table salt is a familiar ionic compound formed from sodium and chlorine. Sodium forms an ion with a single positive charge Na+and chlorine an ion with a single negative charge Cl-. The formula of salt is NaCl.
Is Sugar an Ionic Compound?Sugar easily dissolve in water when we stir but its not an ionic compound. Sugar has many OH groups which forms hydrogen bonds to water and hence its very soluble in water.Ionic Compound NomenclatureBack to Top
An ionic compound contains a metal and a nonmetal.Ionic compounds are also known as salts.An ionic compound is designated by giving the name of the cation first and then the name of the anion.
The nomenclature of ionic compounds involves three kinds of compounds
1. Binary compounds (only two elements)2. Compounds of polyatomic ions (two or more elements that stay together and act as though they are one ion).3. Compounds of multivalent ions (contains more than one charge)Ionic Compound PracticeBack to Top
Example problems are given based on ionic compound.Solved ExamplesQuestion1:Write the formula for these binary ionic compounds.
1. Barium hydride2. Sodium fluoride3. Calcium oxide
Solution:Write the formula of the positive ion and then the formula of the negative ion. Remember that the number of positive and negative charges must be equal. Show the ratio of each ion in the formula of the compound by subscripts. Where only one of either ion is present, do not show a subscript.
1. BaH22. NaF3. CaO
Question2:Name these ionic compounds each of which contains a polyatomic ion.
1. NaNO32. CaCO33. (NH4)2SO34. NaH2PO4
Solution:To name ionic compounds containing polyatomic ions, name the positive ion first and then the negative ion, each as a separate word.
1. Sodium nitrate2. Calcium carbonate3. Ammonium sulfite4. Sodium dihydrogen phosphate
Salt and baking powder (sodium bicarbonate) are both ioniccompounds. Anything that is a metal and nonmetal bonded together isan ionic compound.NaCl - sodium chloride - table salt
KCl - potassium chloride - present in "light" salt (mixed with NaCl)
CaCl2 - calcium chloride - driveway salt
NaOH - sodium hydroxide - found in some surface cleaners as well as oven and drain cleaners
CaCO3 - calcium carbonate - found in calcium supplements
NH4NO3 - ammonium nitrate - found in some fertilizersIonic compoundFrom Wikipedia, the free encyclopediaIt has been suggested thatIonic crystalbemergedinto this article. (Discuss)Proposed since June 2014.
This articleneeds additional citations forverification.Please helpimprove this articlebyadding citations to reliable sources. Unsourced material may be challenged and removed.(June 2011)
Thecrystalstructure ofsodium chloride, NaCl, a typical ionic compound. The purple spheres representsodiumcations, Na+, and the green spheres representchlorideanions, Cl.Inchemistry, anionic compoundis achemical compoundin whichionsare held together in a lattice structure byionic bonds. The positively charged ions are calledcationsand the negatively charged ions are calledanions. These can besimple ionswhere a single atom has a charge imbalance, orpolyatomic ionsmade of multiple atoms. Ions in ionic compounds are held together by theelectrostatic forcesbetween oppositely charged bodies. Individual ions can have multiple nearest neighbours, so are not considered to be part of molecules, but instead part of a continuous network. Ionic compounds have high melting and boiling points, and they are hard and very brittle. As solids they are almost alwayselectrically insulating, but whenmeltedordissolvedthey become highlyconductive, because the ions are mobilized.Contents[hide] 1Nomenclature 2Characteristics 3Structure 4Solubility 5Electrical conductivity 6See also 7References 7.1BibliographyNomenclature[edit]According to thenomenclaturedefined byIUPAC, in the most simple case of a binary ionic compound with no possible ambiguity about thestoichiometry, the common name is written using two words.[1]The name of the cation comes first, followed by the name of the anion.[2]For example, MgCl2is namedmagnesium chloride, and Na2SO4is namedsodium sulfate(SO42,sulfate, is an example of apolyatomic ion). To obtain theempirical formulafrom these names, the stoichiometry can be deduced from the charges on the ions, and the requirement of overall charge neutrality.If the oxidation state of the cation is ambiguous,Stock nomenclaturerequires theoxidation numberto be written inRoman numeralsin parentheses directly after the name of the anion (without a space separating them). For example, FeSO4is namediron(II) sulfate(with the 2+ charge on theFe2+ions balancing the 2 charge on the sulfate ion), whereas Fe2(SO4)3is namediron(III) sulfate(because the two iron ions in each formula unit have a charge of 3+, to balance the 2 on each of the three sulfate ions). If the Classical naming system is being used, some ionic compounds have special "old" names, such as ferrous and ferric, for iron(II) and iron(III) respectively, and cuprous and cupric, for copper(I) and copper(II) respectively, so under that system Fe2(SO4)3is named ferric sulfate.Characteristics[edit]Ions can be single atoms, as thesodiumandchlorinein common table saltsodium chloride, or more complex groups such as thecarbonateincalcium carbonate. But to be considered an ion, they must carry a positive or negative charge. Thus, in an ionic bond, one 'bonder' must have a positive charge and the other a negative one. By sticking to each other, they resolve, or partially resolve, their separate charge imbalances. Positive to positive and negative to negative ionic bonds do not occur.Chemical compounds are never strictly ionic. Even the mostelectronegative/electropositivepairs such ascaesium fluorideexhibit a degree of covalency. Similarly,covalent compoundsoften exhibit charge separations. See alsoHSAB theory.Ionic compounds have very strongelectrostatic bondsbetween particles. As a result, they generally have very high melting and boiling points and a low vapour pressure.[3]They also have good electrical conductivity when molten or in anaqueous solution.[4]Ionicinorganic compoundstypically have high melting points so are solids at room temperature and usually form crystals. Unlikeorganic compoundsthey do not char nor ignite. On the other handorganic compoundshave low melting points, most of them are insoluble in water, and characteristically they ignite quite easily.[5]The ions produced by electron transfer attract each other by electrostatic attraction and this creates an ionic bond.Structure[edit]Ions typically pack into extremely regular crystalline structures, in an arrangement that minimizes theCoulomb energy(maximizing attractions and minimizing repulsions). For spherical ions (including all simple ions), the arrangement of anions in these systems are often related toclose-packedarrangements of spheres, with the cations occupyinginterstices. Depending on thestoichiometryof the ionic compound, and the coordination (principally determined by thesizeratio) of cations and anions, a variety of structures are commonly observed.[6]Common ionic compound structures with close-packed anions[6]
StoichiometryCation:anion coordinationInterstitial sites occupiedCubic close packingHexagonal close packing
MX6:6all octahedralsodium chloridenickel arsenide
4:4alternate tetrahedralzinc blendewurtzite
MX28:4all tetrahedralfluorite
6:3half octahedral (alternate layers fully occupied)cadmium chloridecadmium iodide
MX36:2one-third octahedralchromium(III) chloride[7]bismuth iodide
M2X36:4two-thirds octahedralcorundum
ABO3two-thirds octahedralilmenite
AB2O4one-eighth tetrahedral and one-half octahedralspinel,inverse spinelolivine
In some cases the anions take on a simple cubic packing, and the resulting common structures observed are:Common ionic compound structures with simple cubic packed anions[7]
StoichiometryCation:anion coordinationInterstitial sites occupiedExample structure
MX8:8all filledcesium chloride
MX28:4half filledcalcium fluoride
M2X4:8half filledlithium oxide
Solubility[edit]Following the aphorism, "like dissolves like", ionic compoundsdissolvemost readily inpolar solvents(such aswater) orionic liquids. Ionic compounds tend not to dissolve innonpolar solvents(such asdiethyl etherorpetrol/gasoline).When the oppositely charged ions in the solid ionic lattice are surrounded by the opposite pole of a polar molecule, the solid ions are pulled out of the lattice and into the liquid. When this force is more than the electrostatic attraction of the lattice, the ions become dissolved in the liquid.Electrical conductivity[edit]Although ionic compounds contain charged atoms or clusters, they do not typicallyconduct electricitywhen they are in thesolid state. In order to conduct, the charged particles must bemobilerather than stationary in acrystal lattice. When the ionic compounds aredissolved in a liquidor are themselves melted into aliquid, they can conduct electricity because the ions become mobile.[8]In some unusual materials,fast ion conductors, one or more of the ionic components in the solid phase has a significant mobility, allowing conductivity.What are Some Examples of Covalent Compounds?Covalent Compounds
By Anne Marie Helmenstine, Ph.D.
Chemistry Expert
Share thisAds Ionic Bond Bonding Chemistry Science Compound Chemistry OnlineCHEMISTRY CATEGORIES Chemistry 101 Chemistry Tests and Quizzes Demonstrations - Experiments Periodic Table and the Elements Chemistry Disciplines - Branches of Chemistry Chemistry Homework Help Molecules and Compounds Grow Crystals Science Fair Projects Chemistry for Kids Chemistry in Everyday Life Toxic Chemicals and Safety Chemistry Laboratory Careers and Education Chemistry Facts and Pictures Chemistry Basics Science Demonstrations, Experiments, and Projects Science Fair Ideas and Help Updated Articles and ResourcesVIEW MOREFREE EMAIL NEWSLETTERTop of FormLet About.com send youthe latest from ourChemistry Expert.SIGN UPYou can opt-out at any time.Please refer to ourprivacy policyfor contact information.Bottom of Form
Ethyl alcohol or ethanol is an example of a molecular compound containing atoms joined by covalent bonds.Ben MillsThese are examples of covalent bonds and covalent compounds. Covalent compounds also are known as molecular compounds. Organic compounds, such as carbohydrates, lipids, proteins and nucleic acids, are all examples of molecular compounds. You can recognize these compounds because they consist of nonmetals bonded to each other.PCl3CH3CH2OHO3- ozoneH2- hydrogenH2O - waterHCl - hydrogen chlorideCH4- methaneNH3- ammoniaCO2- carbon dioxide
Ionic compounds include many everyday's substances that we are familiar with table salt (NaCl), baking soda (NaHCO3), milk of magnesia (Mg(OH)2) and calcium carbonate (CaCO3) used as antacids. Ionic compounds also include ionic crystals such as those found in naturally occurring gems, including ruby (Al2O3) and sapphires. - ionic compounds are generically called salts.
Covalent CompoundsCovalent compounds are more predominant than ionic compounds and are made of elements that are non-metals. They include substances that we already know such as water (H2O), table sugar (sucrose = C12H22O11), propane gas (C3H8), and drugs such as the antibiotic amoxicillin (C16H19N3O5S) and the antidepressant Prozac (C17H18F3NO). - covalent compounds are referred to as molecules.PCl3CH3CH2OHO3- ozoneH2- hydrogenH2O - waterHCl - hydrogen chlorideCH4- methaneNH3- ammoniaCO2- carbon dioxideMore Bonding ExamplesExamples of Ionic Bonds - Ionic CompoundsExamples of Compounds with Mixed BondsLearn About Chemical BondingTypes of Chemical BondsDifference Between Ionic and Covalent BondsTypes of Bonds Formed by CarbonVideo - Ionic Versus Covalent BondOnline Chemistry Text - Chemical Bonds
Sodium bromide is used in conjunction with chlorine as a disinfectant for swimming pools.Potassium sulfideis theinorganic compoundwith the formula K2S. The colourless solid is rarely encountered, because it reacts readily with water, a reaction that affordspotassium hydrosulfide(KSH) and potassium hydroxide (KOH). Most commonly, the term potassium sulfide refers loosely to this mixture, not the anhydrous solid.Use in fireworks[edit]Potassium sulfides are formed whenblack powderis burned and are important intermediates in many pyrotechnic effects, such as senko hanabi and some glitter formulations.[3]UsesThismedicationis a mineral used to treat or prevent low levels of zinc.OTHER USES: This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by yourhealth careprofessional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.This medication may also be used to promote wound healing.Ammonium phosphates are inorganic salts derived from the reaction between ammonia and phosphoric acid. They are produced as solids and fluids and they may contain phosphate values in ortho- (usually solid) and/or polyphosphate (usually fluid) form. The vast bulk of ammonium phosphate products are produced and consumed as solid materials. This report concentrates on the use of ammonium phosphates as fertilizers, which accounts for nearly 98% of total use, but brief mention is made of animal feed and industrial uses in the United States.The following pie chart shows world consumption of all solid ammonium phosphates:
Apparent world consumption of solid ammonium phosphate grew at an average annual rate of 2.6% during 19932013, but grew at 3.4% during 19992013. Growth is forecast at 3.5% annually during 20132018. Ammonium phosphates will continue to grow at a faster rate than other complex phosphate materials.Ammonium phosphates are consumed primarily in fertilizer applications, although minor amounts are used in animal feeds and industrial applications. The leading industrial applications include fire control and flame-retardant applications. Animal feed and industrial applications combined consume less than 3% of total world apparent consumption.Chromate conversion coatingis a type ofconversion coatingused topassivatealuminum,zinc,cadmium,copper,silver,magnesium, andtinalloys.[1]It is primarily used as acorrosion inhibitor,primer, decorative finish, or to retainelectrical conductivity. The process is named after thechromatefound inchromic acid, also known ashexavalent chromium,[2]the chemical most widely used in the immersion bath process whereby the coating is applied. However, hexavalent chromium is toxic, thus, highly regulated,[3]so new, non-hexavalent chromium-based processes are becoming more readily available at a commercial level.[4]One alternative containstrivalent chromium. TheRoHS(Restriction of Hazardous Substances) Directive is commonly referred to regarding elimination of hexavalent chromium.Chromate conversion coatings are commonly applied to everyday items such as hardware and tools, and can usually be recognized by their distinctively iridescent, greenish-yellow color.Ozonecan beusedfor combustion reactions and combusting gases;ozoneprovides higher temperatures than combusting in dioxygen (O2).Hydrogen is the lightest and most common element in the cosmos. Its atomic number is 1. In its elemental state, hydrogen is rare. But it is one of the components of water and vital to life.Common Uses of HydrogenIt is primarily used to create water. Hydrogen gas can be used for metallic ore reduction. Chemical industries also use it for hydrochloric acid production. The same hydrogen gas is required for atomic hydrogen welding (AHW).
