0 g 2 g 5 g 10 g 15 g Boiling temperature, ºC a. Line graph c. Bar graph b. Circle graph d.

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1 Name: Key Block: Date: Honors Chemistry Fall Final Review This is your review for your fall final. These questions are meant to prepare you for the type of questions and topics you will see on your final. Use your notes, assignments, and textbook (chapters 2-8) in helping answer these questions and prepare for your final. Good luck! And remember to sleep and eat well; a tired and hungry brain is not a smart brain. Unit 1 1. Which kind of graph would be best to use with these data? Amount of Salt Added 0 g 2 g 5 g 10 g 15 g Boiling temperature, ºC a. Line graph c. Bar graph b. Circle graph d. None of the above 2. Look at the table of density data for an unknown substance. Based on the table, the mass of 11 ml of this substance would be 32.4 g. Density Data Volume (ml) Mass (g) A metal cube has a mass of 54 g and a volume of 20.0 cm 3. Is this metal composed of pure aluminum? Explain. (density of aluminum is 2.7 g/cm 3 ) 54 = g/cm3 Yes, this is pure aluminum because they density is the same. 4. A car covers a distance of km in 1.8 hours. Calculate its speed in meters per second km 0 m 1 hr 1 min = m/sec 1.8 hr 1 km 60 min 60 sec 5. How long would it take (in hours) an airplane traveling at the speed of sound (740 miles per hour; mach 1 ) to travel around the earth, at the equator? The circumference of the earth is 25,000 miles. 25,000 mi 1 hr = hours 740 mi 6. A common unit of power is the watt: 1 watt = 1 amp volt. Ordinary house current is 120 volts. How many amps of current are drawn by a 60 watt light bulb? 60 watt 1 amp volt = 0.5 amps 1 watt 120 volt

2 Unit 2 7. Rocky Road ice cream is a heterogeneous mixture. 8. Which is a chemical property of copper? a. Has a boiling point of 2567ºC c. Has the symbol Cu b. Reacts in air to form a green layer d. Is a solid at room temperature 9. The accepted value is Which correctly describes this student s experimental data? Trial Measurement a. Accurate but not precise c. Both accurate and precise b. Precise but not accurate d. Neither accurate nor precise 10. The accepted value is Which correctly describes this student s experimental data? Trial Measurement a. Accurate but not precise c. Both accurate and precise b. Precise but not accurate d. Neither accurate nor precise 11. The accepted value for a quantity is 5.67 g. If the measure value is 5.89 g, what is the percent error? a. 1.04% c. 3.74% (I got 3.88% on my calculator) b. 96.3% d % (can t have a negative % error) 12. Samples of gases containing nitrogen and oxygen were decomposed by electricity and the volume of each gas produced was measured. Based on these results, which is the correct chemical formula for Sample 4? Gas Samples Sample Volume of Nitrogen (L) Volume of Oxygen (L) a. N2O2 c. NO2 b. NO d. N2O 13. Which is a compound? a. Sodium c. carbon dioxide b. Sea water d. brass 14. According to the Law of Conservation of Mass, in any chemical change a. The mass of reactants is greater than the mass of products b. The mass of reactants is less than the mass of products c. The mass of reactants is equal to the mass of products d. The masses of products and reactants have no predictable relationship

3 15. A chemical composition of two or more different elements joined together in fixed proportions is known as a(n). a. Compound c. Homogeneous mixture b. Element d. Heterogeneous mixture 16. Which scientist described a positively charged core ( nucleus ) in the middle of a lot of empty space? a. Chadwick c. Rutherford b. Thomson d. Bohr 17. Which scientist developed the model of the atom shown? a. Chadwick c. Rutherford b. Thomson d. Bohr 18. Which two have the same mass? Atoms Atom Proton Neutron Electron a. Atoms 1 & 2 c. Atoms 1 & 4 b. Atoms 2 & 4 d. Atoms 2 & Atoms with the same number of protons but different number of neutrons are called isotopes. 20. An alpha particle is positively charged. (a helium nucleus, 2 protons and 2 neutrons) 21. If 19.9 grams of copper are burned in air to produce 25.0 grams of copper oxide, what is the mass of oxygen from the air that is needed? = 5.1 g of oxygen 22. What is the average atomic mass of the element? Isotope Mass (amu) Percent Abundance Phosphorus % Phosphorus % Phosphorus % = amu 23. What is the percentage by mass of A if 4.07 g of it reacts with g of X to form a compound of mass g? Also, calculate the percentage by mass of X in the compound. A: =.2769 = 27.69% X: =.7231 = 72.31%

4 24. Two different compounds are formed by the elements nitrogen and oxygen. The first compound, compound P1, contains 64.17% by mass nitrogen and 35.73% by mass oxygen. The second compound, compound P2, contains 47.21% by mass nitrogen and 52.79% by mass oxygen. What is the ratio of nitrogen to a fixed mass of oxygen for the two compounds? (There were typos in the question, those have been corrected above sorry) = = = :1 ratio nitrogen to oxygen An element X has three naturally occurring isotopes: X-24, X-25, and X-26. The atomic mass of X-25 is amu and the relative abundance is 10.00%. The atomic mass of X-26 is amu and the relative abundance is 11.01%. Given that the weighted atomic mass of the element X is , calculate the mass contribution due to the isotope X-24 and identify the element = 78.99% abundance X X = X = X = X = amu mass of X-24 XX = amu 26. What were the results of Rutherford s gold foil experiment? What did these results disprove? From doing the gold foil experiment, Rutherford concluded that atoms are composed of a small, positively charge nucleus with negatively charged particles surrounding it. His results disproved Thompson s plum-pudding model that stated the atom was a large positively charged area with negative particles distributed throughout. 27. A researcher s experiment yields a result that is 4.7% to high. Her result was 47.2 g for the mass. EEEEEEEEEEEEEEEEEEEEEEEE AAAAAAAAAAAA Calculate the actual mass. ( ) AAAAAAAAAAAA 47.2 AA AA 47.2 AA AA = 4.7% = A = 0.047A 47.2 = 1.047A A = 45.1 g Unit Which element has the electron configuration 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 4? a. Titanium (Ti) c. Sulfur (S) b. Chromium (Cr) d. Selenium (Se) 29. How many valence electrons are in an atom of neon gas? a. 2 b. 4 c. 6 d. 8

5 30. Which diagram correctly depicts the trend in electronegativity? B 31. Which diagram correctly depicts the general trend in first ionization energy? B 32. Which element has an electron configuration that ends in the fourth energy level? A D B C 33. As the frequency of a wave decreases, the wavelength of the wave increases. 34. List the visible spectrum in order of greatest energy, shortest wavelength, and greatest frequency. HHHHHHh EEEEEEEEEEEE LLLLLL EEEEEEEEEEEE SShoooooo WWWWWWWWWWWWWWWWWWh Violet, indigo, blue, green, yellow, orange, red LLLLLLLL WWWWWWWWWWWWWWWWWWh HHHHHHh FFFFFFFFFFFFFFFFFF LLLLLL FFFFFFFFFFFFFFFFFF 35. Why is the size of a sodium ion (Na + ) less than that of a sodium atom (Na)? The sodium ion loses an electron. When it does so the electron configuration goes from 1s 2 2s 2 2p 6 3s 1 to 1s 2 2s 2 2p 6 dropping the sodium ion from the third energy level to the second. Because it is losing an energy level, the sodium ion is small in size than the neutral sodium atom. 36. Name or write the formula for the following compounds: a. Cl2O7 Dichlorine heptoxide f. beryllium sulfate BeSO 4 b. H 2 SO4 Sulfuric acid g. carbon tetrachloride CCl 4 c. HI Hydroiodic acid h. chromium (III) oxide Cr2O3 d. NH 4 Cl Ammonium chloride i. hydrobromic acid HBr e. Pb(C2H3O2)4 Lead (IV) acetate j. nitric acid HNO 3

6 Unit Which structure is the MOST correct for C3H5? Explain why. The second structure is the most correct because it shows the resonance of the structure since the double bond can (and does) exist between each set of carbons at any point in time. You would also draw this structure like the one below (on your final ) 38. Choose the correct order from least to greatest electronegativity a. F< O< Be< Li <B c. Li <Be <B< O< F b. Be<O <Li< F <B d. F< Be <B <O <Li 39. What is the electronegativity difference in the bonds for the following compounds (see the chart on the reference page): a. CO = 0.89 Polar b. Al2O = 2.28 Ionic c. PCl = 0.97 Polar 40. For the following compound, give the name, total number of valence electrons, structural formula, shape, and polarity: a. NH2 - Nitrogen dihydride ion Bent N: 5 1 = 5 Polar H: 1 2 = 2-1 charge = 1 8 valence e - b. BF 3 Boron trifluoride Trigonal planar B: 3 1 = 3 Nonpolar F: 7 3 = valence e - c. FNO 2 Fluoride nitrogen dioxide Trigonal planar F: 7 1 = 7 Polar N: 5 1 = 5 F: 6 2 = valence e - + d. XeF 5 Xenon pentafluoride Square Pyramidal Xe: 8 1 = 8 Polar F: 7 5 = charge = valence e -

7 Reference Page Element Electronegativity Carbon 2.55 Oxygen 3.44 Sulfur 2.58 Fluorine 3.98 Nitrogen 3.04 Phosphorous 2.19 Aluminum 1.16 Chlorine 3.16 bent