CHAPTER 7: CHEMICAL FORMULAS AND COMPOUNDS TEST REVIEW SHEET

1. A chemical formula includes the symbols of the elements in the compound and subscripts that indicate___ 2. What is the formula for sulfur dichloride? 3. How many atoms of fluorine are present in a molecule of carbon tetraflouride, CF4? 4. What is the formula for the compound formed between calcium ions and chloride ions? 1. Number of atoms or ions of each elements that are combined in the compound. 2. SCl2 3. 4 4. CaCl2

5. Ba(OH)2 6. Nickel (II) Chlorate 7. Potassium Chlorate 5. What is the formula for barium hydroxide? 6. Name the compound Ni(ClO­3)2. 7. Name the compound KClO3   8. Name the compound SiO2 (Si is on the right side of the metal/nonmetal line 5. Ba(OH)2 6. Nickel (II) Chlorate 7. Potassium Chlorate 8. Silicon Dioxide

9. +1 10. Sulfur Trioxide 11. PbCrO4 12. Al2(SO4)3 9. What is the oxidation number of hydrogen in H2O?   10. Name the compound SO3 11. What is the formula for the compound formed by lead (II) ions and chromate ions? 12. What is the formula for aluminum sulfate? 9. +1 10. Sulfur Trioxide 11. PbCrO4 12. Al2(SO4)3

13. Dinitrogen Trioxide 14. SiO2 15. Zinc Phosphate 16. N2O3 13. Name the compound N2O3 14. What is the formula silicon dioxide?   15. Name the compound Zn3(PO4)2 16. What is the formula for dinitrogen trioxide? 13. Dinitrogen Trioxide 14. SiO2 15. Zinc Phosphate 16. N2O3

17. What is the formula for diphosphorus pentoxide?   18. What is the formula for hydrochloric acid? 19. The oxidation number of fluorine is? 20. What is the oxidation number of a pure element or unbounded element ex. Na 17. P2O5 18. HCl 19. -1 20. 0

21. The charge of the compound 21. In a compound, the algebraic sum of the oxidation numbers of all atoms equals   22. Name the compound Al2S3 23. Name the compound Fe(NO3)2 24. Name the compound CF4 21. The charge of the compound 22. Aluminum Sulfide 23. Iron (II) Nitrate 24. Carbon Tetrafluoride

25. The charge of the ion 26. -1 27. 95.21 (24.3 + (2x35.5) ) 28. +6 25. In a polyatomic ion, the algebraic sum of the oxidation numbers of all the atoms is equal to? 26. What is the oxidation number of hydrogen in KH? 27. What is the formula mass of magnesium chloride, MgCl2?   28. What is the oxidation number of sulfur in H2SO4 25. The charge of the ion 26. -1 27. 95.21 (24.3 + (2x35.5) ) 28. +6

29. Name the compound SO2   30. The formula for carbon dioxide, CO2, can represent 31. Name the compound CCl4 32. Name the compound CO2 29. Sulfur Dioxide 30. One molecule of carbon dioxide, 1 mol of carbon dioxide molecules ,The combination of 1 atom of carbon and 2 atoms of oxygen 31. Carbon Tetrachloride 32. Carbon Dioxide

33. Mole of the element 34. 2.498 mol (114.95/46.01) 33. The molar mass of an element is the mass of one 34. The molar mass of NO2 is 46.01 g/mol. How many moles of NO2 are present in 114.95 g?   35. The molar mass of CCl4 is 153.81 g/mol. How many grams of CCl4 are needed to have 5 moles? 36. The molar mass of H2O is 18.02 g/mol. How many grams of H2O are present in .20 moles? 33. Mole of the element 34. 2.498 mol (114.95/46.01) 35. 769.05 g (153.81x5) 36. 3.6 g (18.02x.20)

(12.011/TOTAL)X100 AND (15.999/TOTAL)X100 37. What is the percent composition of CF4?   38. What is the percent composition of CO? 39. The formula that shows the simplest whole-number ratio of the atoms in a compound is the 37. 13.6% C, 86.4%F (12.011+(18.998X4) ) THEN, (12.011/TOTAL)X100 AND (18.998X4)/TOTALX100 43% C, 57% O (12.011+15.999) THEN, (12.011/TOTAL)X100 AND (15.999/TOTAL)X100 39.EMPIRICAL FORMULA

40. Smallest whole-number ratio of the atoms 40. The empirical formula for a compound shows the symbols of the elements with subscripts indicating the __________ 40. Smallest whole-number ratio of the atoms 41. A compound contains 64 g of O and 8 g of H. What is the empirical formula for this compound? 41. H20 64+8=72 g TOTAL. (64/72)X100 =88.8% 88.8X(1/16) = 5.55 / 5.55 = 1 (8/72)X100=11.1% 11.1X(1/1) = 11.1 / 5.55 = 2

42. An oxide of Chromium is found to have the following % composition: 68.4% Cr and 31.6% O. What is the compound’s empirical formula? 43. A compound has an empirical formula of NH2 and a formula mass of 32.06 amu. What is the compound’s molecular formula?   42. Cr2O3 68.4x(1/51.99) = 1.32 / 1.32 = 1 x 2 = 2 31.6x(1/15.99)=1.98 / 1.32 = 1.5 x 2 = 3 43. N2H4 (14.007+(1.0079X2) ) =16.0228 THEN 32.06/16.0228 = 2 SO 2 X NH2

44. The empirical formula of a hydrocarbon is found to be CH 44. The empirical formula of a hydrocarbon is found to be CH. Laboratory procedures have found that the molar mass of this compound is 78 g/mol. What is the correct molecular formula of this compound? 44. C6H6 (12.011+1.0079)=13.0189 78/13.0189 = 6 SO 6xCH = C6H6