Worksheet #6

Covalent (Molecular) Compounds 1. What happens when a covalent bond is formed? What keeps the species together in a covalent bond?

Binary Compounds with 2. Write correct names for the following compounds: a) HCl; b) H2S; c) HBr; d) HF; e) H2Se.

3. Write correct formulas for the following compounds: a) ; b) ; c) hydrogen ; d) hydrogen .

Naming Covalent Compounds 4. Write correct names for the following compounds: a) CS2; b) SiF4; c) ClF5; d) SO2; e) N2O5; f) PCl5; g) SiO2; h) Cl2O6; i) S2Cl2; j) SF4.

5. Write correct formulas for the compounds: a) tricarbon ; b) trichloride; c) dinitrogen trioxide; d) tetraphosphorous trisulfide; e) hexafluoride; f) iodine trichloride; g) disulfur decafluoride; h) phosphorous pentafluoride; i) monoxide; j) dinitrogen monoxide.

Naming Acids 6. Write correct names for the following compounds: a) H2SO4; b) HNO3; c) HClO; d) HClO4; e) CH3CO2H.

7. Write correct formulas for the following compounds: a) hydrocyanic acid; b) phosphoric acid; c) chlorous acid; d) carbonic acid; e) ; f) chromic acid.

Chapter 9 – Simple Inorganic Nomenclature Section A

Write the symbol for the following elements. 1. calcium 2. iodine 3. antimony

Section C Name the following compounds. 7. NaOH 8. NH4CN 9. Fe2S3

Give the formulas for the following compounds. 10. ammonium hydroxide 11. 12. sodium peroxide

Name the following compounds. (Use the Greek count of atoms.) 13. TiCl4 14. PbO3 15. BF3

Give the formulas for the following compounds. 16. phosphorus pentoxide 17. silicon tetrachloride 18. sulfur trioxide

Section D Name the following oxyacids. 19. HNO2 20. H2CrO4 21. HlO4

Give the formulas for the following acids. (Note: Some are unstable or don’t exist.) 22. phosphorous acid 23. 24. chlorous acid

Section E Name the following anions. - 25. NO3 2- 26. SO4 2- 27. Cr2O7

Give formulas for the following anions. Show the charge. 28. sulfite 29. chlorite 30. acetate

Section F Name the following compounds. 31. Ca3(PO4)2 32. Al(ClO3)3 33. CuSO4

Write the formulas for the following compounds. 34. sodium dichromate 35. copper(II) nitrate 36. tin(II) phosphate

Answers to Worksheet #6

Covalent (Molecular) Compounds 1. When a covalent bond is formed, nonmetals share electrons. The electrons act as glue to keep the atoms together.

Binary Compounds with Hydrogen When naming binary (two elements, here H + 1 other element) compounds containing hydrogen and another nonmetal, name the hydrogen first, and then name the nonmetal as if it were an anion. In other words, change its ending to “ide”. When making formulas from names, assume that hydrogen has a +1 charge and give the other nonmetal the charge it would normally get. Remember to balance the charges so that the net charge is zero.

2. a) ; b) ; c) ; d) hydrogen fluoride; e) hydrogen selenide. 3. a) HI; b) HF; c) H2S; d) H2Se.

Naming Covalent Compounds Name the element with the lowest group number first (exception: If a compound contains only a halogen and oxygen, name the halogen first). The lowest group number element keeps its name. If there is more than one of the lower group element, use the prefixes below, which you should memorized (do not use mono). The higher group number element changes its ending to “ide”. Always use the prefixes for the higher group number element. Example: CO2. C is the lower group number, so it will be named first and will keep its name. There is only one of it, so a prefix will not be used. O is the higher group number so it will be named second and the prefix di will be used. CO2 is carbon dioxide.

To write formulas from names, write the elements in order of appearance, and give subscripts equal to the prefixes. Example: dinitrogen tetraoxide. Nitrogen will be written first, and there are two of them. Oxygen will be written second and there are four of them. Dinitrogen tetraoxide is N2O4.

Prefixes: 1 = mono; 2 = di; 3 = tri; 4 = tetra; 5 = penta; 6 = hexa; 7 = hepta; 8 = octa; 9 = nona; 10 = deca.

4. a) carbon disulfide; b) silicon tetrafluoride; c) chlorine pentafluoride; d) ; e) dinitrogen pentoxide; f) phosphorous pentachloride; g) silicon dioxide; h) dichlorine hexoxide; i) disulfur dichloride; j) .

5. a) C3S2; b) BrCl3; c) N2O3; d) P4S3; e) SF6; f) ICl3; g) S2F10; h) PF5; i) ClO; j) N2O.

Naming Acids Naming Polyatomic Acids: Acids containing a polyatomic are named according to the name of the polyatomic ion. If the polyatomic ion’s name ends in “ite” change it to “ous” - and put the second word acid. (Example: HNO2 – NO2 is nitrite, so the name will be nitrous acid.) If the polyatomic ion’s name ends in “ate” change it to “ic” and put the - second word acid (remember: I ate an icky bug). (Example: HNO3 – NO3 is nitrate, so the name will be nitric acid.). The only exception to this is hydrocyanic acid, HCN, which gets the prefix hydro along with the ending change.

To write formulas from names, balance the charge of the polyatomic ion with H+, remembering to always write the H first. So, chloric acid: the ending is ic, so the - + polyatomic ion is chlorate, ClO3 . One H is needed to balance the -1 charge on chlorate, so chloric acid is HClO3.

6. a) sulfuric acid; b) nitric acid; c) ; d) perchloric acid; e) acetic acid

7. a) HCN; b) H3PO4; c) HClO2; d) H2CO3; e) H2SO3; f) H2CrO4.

Answers to Chapter 9 – Simple Inorganic Nomenclature Section A 1. Ca 2. l 3. Sb

Section C 7. sodium hydroxide 8. ammonium cyanide 9. iron(III) sulfide (or ferric sulfide)

10. NH4OH 11. CaS 12. Na2O2

13. titanium tetrachloride 14. lead dioxide 15. boron trifluoride

16. P2O5 17. SiCl4 18. SO3

Section D 19. nitrous acid 20. chromic acid 21. periodic acid

22. H3PO3 23. H2SeO4 24. HClO2

Section E 25. nitrate 26. 27. dichromate

2- 28. SO3 - 29. ClO2 - 30. C2H3O2

Section F 31. calcium phosphate 32. aluminum chlorate 33. copper(II) sulfate (or cupric sulfate)

34. Na2Cr2O7 35. Cu(NO3)2 36. Sn3(PO4)2