Naming Inorganic Compounds. common names systematic names

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1 Naming Inorganic Compounds common names systematic names

2 Molecular Common Systematic Formula name name AgCl Lunar caustic Silver chloride H 2 SO 4 Oil of vitriol Sulfuric acid MgSO 4 Epsom salts Magnesium sulfate

3 Nonenclature When naming chemical compounds we distinguish between Organic compounds - compounds containing carbon. Exceptions: CO, CO 2, CS 2, CN -, CO 3 2-, HCO 3-, H 2 CO 3 Inorganic compounds - all other compounds

4 we can break the naming of inorganic compounds into four categories: Ionic compounds Molecular compounds Acids and Bases Hydrates

5 Naming binary ionic compounds binary compounds contain two elements and are named as two words first word is name of more electropositive element second word is first part of name of more electronegative element followed by -ide

6 Example Write the formulas for the following compounds: (a) potassium sulfide K + S 2 Answer: K 2 S

7 Binary compounds of metals (cont d) When metal can form more than one type of cation, indicate charge by Roman numeral in parenthesis MnO Mn 2 O 3 MnO 2 manganese(ii) oxide manganese(iii) oxide manganese(iv) oxide use of the suffixes -ous and -ic is discouraged

8 Example Write the formulas for the following compounds: (a) tin(ii) fluoride Sn 2+ F Answer: SnF 2

9 Example Write the formulas for the following compounds: (a) mercury(ii) oxide Hg 2+ O 2 Answer: HgO

10 Polyatomic Ions molecules with a charge : : O : O: : : : S O : : O : (SO 4 2- )

11 Polyatomic Ions (CO 2-3 ) (CrO 2-4 ) (OH - ) (NO - 3 ) (Cr 2 O 2-7 ) carbonate chromate hydroxide nitrate dichromate (ClO 3 - ) chlorate

12 bromate (BrO 3 - ) Iodate (IO 3 - ) peroxide O 2 2 O O acetate C 2 H 3 O 2 H O H C C O H

13 Example Name the following ionic compounds: (a) Cu(NO 3 ) 2 Cu 2+ 2NO - 3 Answer: copper(ii)nitrate

14 Naming Molecular Compounds

15 Molecular Compounds Electrons are shared by the atoms. Covalent Bonds Electrons however are not shared equally.

16 δ+ H 105 H δ+ O 2δ

17 naming binary compounds of nonmetals 1) more electropositive element named first (and listed first in chemical formula) 2) more electronegative element named in usual way (with -ide suffix) 3) counting prefixes are used with each name but mono is not used with first name

18 Greek prefixes used in naming molecular compounds Prefix Meaning Prefix Meaning Mono- 1 Hexa- 6 Di- 2 Hepta- 7 Tri- 3 Octa- 8 Tetra- 4 Nona- 9 Penta- 5 Deca- 10

19 Name the following compounds ClF 3 SCl 2 chlorine trifluoride sulfur dichloride Cl 2 O 7 dichlorine heptoxide

20 Naming Acids Naming an acid depends on whether the anion contains oxygen If the anion does not contain oxygen the acid is named with the prefix hydro and the suffix --ic If the anion contains oxygen the acid name is formed from the root name of the anion with the suffix -ic or -ous

21 Names for some binary acids Anion Corresponding Acid F (fluoride) HF (hydrofluoric acid) Cl (chloride) HCl (hydrochloric acid) Br (bromide) HBr (hydrobromic acid) I (iodide) HI (hydroiodic acid) CN (cyanide) HCN (hydrocyanic acid) S 2 (sulfide) H 2 S (hydrosulfuric acid)

22 Ternary acids three element acids most ternary acids are oxyacids containing hydrogen, oxygen, and one other element

23 Oxyacids acetate anion acetic acid H O H O H C C O H C C O H H H

24 Oxyacids perchlorate ClO 4 perchloric acid HClO 4 HOClO 3 Addition of one O atom chlorate ClO 3 chloric acid HClO 3 removal of one O atom HOClO 2 chlorite ClO 2 chlorous acid HClO 2 HOClO removal of two O atoms hypochlorite ClO hypochlorous acid HOCl

25 Hydrates Compounds that have a specific number of water molecules attached to them Copper(II) sulfate pentahydrate CuSO 4 5H 2 O Copper(II) sulfate anhydrous CuSO 4 Anhydrous - the water molecules have been driven off by heating

26 Chemical Equations shows the results of a chemical process reactants (reagents) products coefficients the numbers in front of formulas in chemical equations gives the relative number of molecules taking part in a reaction

27 Skeleton Equations is a term which describes using chemical formulas rather than words to identify the reactants and products 2H (g) 2 + O (g) 2 2H 2 O(g) Chemical bonds have been broken and new chemical bonds have been formed

28 Writing Chemical Equations 2H 2 (g) + O 2 (g) 2H 2 O(g) g g g Parentheses show physical state of substances

29 physical state of substances (s) = solid (l) = liquid (g) = gas (aq) = aqueous (dissolved in water)

30 Example mass interpretation 2H 2 + O 2 2H 2 O 4 g 32 g 36 g Start: 4g 32g 0 Finish: g

31 The law of conservation of mass requires that chemical equations must balance. What goes in Must come out

32 Writing and balancing the equation for a chemical reaction 1. Identify all reactants and products and write their correct formulas on the left side and right side of the equation, respectively. 2. Begin balancing the equation by trying suitable coefficients that will give us the same number of atoms of each element on both sides of the equation. Change coefficients, but not subscripts. 3. Look for elements that appear only once on each side of the equation. Balance these first. 4. Check.

33 Example Balance the following equation Fe 2 O 3 + CO 2Fe + 2CO 2

34 Example Balance the following equation Fe 2 O 3 + 3CO 2Fe + 3CO 2

35 Example Balance the following equation NH 3 + O 2 NO + H 2 O 2NH 3 + O 2 2NO + 3H 2 O 2NH 3 + (5/2) O 2 2NO + 3H 2 O multiply everything by 2 4NH 3 + 5O 2 4NO + 6H 2 O

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