RESPONSE: B,D,E ANSWER: B,D,E A row is known as a period, so we need all the elements in the same row. POINTS: 1 / 1

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1 Name: Score: 46 / 46 points (100%) 2010 Released SOL Multiple Response Identify one or more choices that best complete the statement or answer the question. Directions: Click on the correct answers. 1. According to the periodic table of the elements, which elements belong to the same period? a. Aluminum d. Arsenic b. Germanium e. Gallium c. Antimony RESPONSE: B,D,E,D,E A row is known as a period, so we need all the elements in the same row. Numeric Response Directions: Type your answer in the box. Use + and for the electrical charge. 2. What is the oxidation number of an oxide ion? RESPONSE: 2 ANSWER: 2 or 2 (oxide is the ionic version of oxygen and group 16 on the periodic table form 2 ions due to the fact that this column has 6 valence electrons and need to gain 2 more electrons. Since electrons are negative, gaining two makes a negative 2 charge). Directions: Type your answer in the box. Your answer must use significant digits. 3. What is the density of an aqueous solution (in g/ml) that has a mass of g and 12.5 ml? RESPONSE: ANSWER:.806 or (D=m/V; D=10.081/12.5= But we also must use sig figs according to the directions has 5; 12.5 has 3 so our answer can only have 3 sig figs) Directions: Type your answer in the box. file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 1/17

2 4. Calculate the number of moles of Li 3 PO 4 in 2.2 L of a 0.60 M Li 3 PO 4 solution. RESPONSE: 1.32 ANSWER: 1.32 Acceptable answers are: 1, 1., 1.3, 1.32, 1.33, 1.4, 2, or 2. M=mol/L 0.60 = x/2.2 x= 1.32 Directions: Type your answer in the box. 5. An expandable container of oxygen gas has a volume of 125 ml at a temperature of 25.0 C. What volume (in ml) will the gas occupy at 55.0 C? RESPONSE: ANSWER: Acceptable answers are: 130, 130., 137, 137., 137.5, 137.6, 138, 138., 140, or 140. First, we need the temperature in Kelvin (+273) for this problem. Then, you can either use the PTV trick I have shown you in class (and below) or you can use the formula V1/T1=V2/T2. =137.6 Directions: Click and drag the correct answers to the boxes. Note that I am unable to have you complete these directions as stated. Instead type your answer exactly as they would appear in the boxes. 6. Create the formula for diboron trioxide using the symbols provided. file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 2/17

3 RESPONSE: B2O3 2O3 First elements need to start with capital letters so we have to use the B and O for boron and oxygen. Second, the prefixes tell you how many of each you have. di means 2 so there are 2 borons while tri means 3, so 3 oxygens. These numbers would appear in the subscript positions. SOL document Here is the screen shot from the released Multiple Choice Identify the choice that best completes the statement or answers the question. C 7. A student measures the mass of a 1.00 g aluminum rod as 0.99g. The best estimate of the percent error associated with this measurement is a. 0.01% c. 1% b. 0.1% d. 10% Percent Error = (Accepted Experimental)/Accepted x 100 ( )/1.00x100=1% B 8. The most efficient way to determine whether a reaction is an exothermic chemical reaction is to use file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 3/17

4 D 9. a. an oxygen probe c. a pressure probe b. a temperature probe d. a ph probe exothermic reactions release heat and will feel warm/hot to the observer. As a result, a temperature probe can be used to determine if the reaction is increasing in temperature. 2Al(C 2 H 3 O 2 ) 3 + 3BaSO 4 Al 2 (SO 4 ) 3 + 3Ba(C 2 H 3 O 2 ) 2 Which type of chemical reaction does this equation represent? a. Synthesis c. Oxidation reduction b. Neutralization d. Double replacement Not Synthesis This type of reaction results in the creation of 1 compound from many reactants Not Neutralization This type of reaction results in an acid (starts with H) and a base (ends with OH) making water (results from the H and OH combining) and a salt Not a Redox (Oxidation reduction) because all the oxidation numbers of the elements stay the same on the reactant and product side It is a double replacement Al and Ba switched the anion they are with. C 10. What is the molarity of a solution with 0.2 moles of potassium permanganate (KMnO4) dissolved in enough water to make a ml solution? a M c. 0.4 M b. 0.1 M d. 100 M molarity is mol/l. M=0.2mol/0.500L=0.4M (500mL > L; you have to divide by 1000) C 11. When 92.0 g of ethanol (C 2 H 5 OH) are vaporized at its boiling point of 78.3ºC, it requires 78.6 kj of energy. What is the approximate molar heat of vaporization of ethanol in kj/mol? a c b d The told you that you need kj/mol, so divide the kj by moles. (Note: temperature doesn t play a part in molar heat of vaporization because heat equals moles times molar heat of vaporization) So, turn the grams to moles 92.0g x ( )=2 mol 78.6kJ/2mol = 39.3 file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 4/17

5 B 12. Which element has 16 neutrons, 15 protons, and 15 electrons? a. Sulfur (S) c. Gallium (Ga) b. Phosphorus (P) d. Zinc (Zn) The important subatomic particle here is the proton. The number of protons = atomic number, which tells you the element is phosphorus (atomic number 15). A 13. Al(s) + 3AgNO 3 (aq) Al(NO 3 ) 3 (aq) + 3Ag(s) This equation represents which type of chemical reaction? a. Single replacement c. Decomposition b. Double replacement d. Synthesis Single replacement element + compound > element + compound Yes Double replacement compound + compound > compound + compound No Decomposition 1 substance breaks down to 2 or more No Synthesis 2 or more substance combine to make 1 No C 14. In the formula for barium chloride, (BaCl 2 ), barium (Ba) is written first because it is a. a single atom c. the positive ion b. a larger ion d. the negative ion When writing a chemical formula, the first ion is positive (the cation) and the second is negative (anion) C 15. Which of these laboratory techniques is best to separate a solid from a liquid to recover the liquid? a. Titration c. Filtering b. Chromatography d. Vaporization Titration experiment usually with acids and bases that is used to determine the concentration of an unknown substance No Chromatography uses a mobile and stationary phase to separate a mixture of various types of phases, but it usually separates gases from gases or liquids from liquids Not the best choice Filtering separates the liquid and the solid. The solid would get stuck in the filter and the liquid is collected in another container Yes Vaporization separates a liquid and a solid by the liquid would escape as it evaporated No file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 5/17

6 A 16. Which of these is NOT required to ensure that stock solutions are free of contamination? a. Store all solutions in brown bottles b. Do not place dropping pipettes in stock solution bottles c. Never return excess chemicals to stock bottles d. Replace tops on reagent bottles after use Store all solutions in brown bottles Colored bottles can help some substances from breaking down, but it is not required to keep contaminants out of the bottle Yes Do not place dropping pipettes in stock solution bottles any contaminant on the pipette would get into the solution and cause contamination No Never return excess chemicals to stock bottles any contaminant on the excess chemicals would get into the solution and cause contamination No Replace tops on reagent bottles after use this would prevent contaminants from falling into the bottle No D 17. Which of these values is most responsible for changing the boiling and freezing points of a solvent? a. Molar mass of the solvent c. Weight of the solute particles b. Electronegativity of the solvent d. Number of solute particles Colligative properties like boiling point elevation and freezing point depression depend on the concentration of the solute in the solvent in molality, so it would be the number of dissolved particles A 18. What is the name of the compound with the formula NH 4 NO 3? a. Ammonium nitrate c. Nitrogen hydrogen oxide b. Nitrogen nitrate d. Ammonium nitrogen trioxide NH 4 + is known as ammonium and NO 3 is called nitrate B 19. N 2 (g) + 3F 2 (g) 2NF 3 (g) Equilibrium has been reached for the reaction shown. Which conclusion is correct? a. The N 2 and F 2 together will form at a faster rate than the NF 3. b. The partial pressures of N 2, F 2, and NF 3 will stay constant. c. The NF 3 will form at a faster rate than the N 2 and F 2 together. d. The partial pressure of NF 3 will keeping changing. Equilibrium is when the forward and reverse rate are equal. With this in mind file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 6/17

7 choice a and c could not be the answer. And according to Le Chatelier s principle, changing the pressure of a system would add stress that would result in the equilibrium to shift. As a result, d would not be an option because this would mean that it wouldn t be in equilibrium. b would have to be the answer because the equal rates would keep the pressures constant. A 20. If 89.6 joules of heat are needed to heat 20.0 grams of iron from 30.0 C to 40.0 C, what is the specific heat of the iron in? a c b d. 896 q=mc p T 89.6=(20)(x)(40 30) 89.6=200x x=89.6/200=0.448 or, they said they wanted the answer in, so if we plug the numbers in their spots = B 21. Which of the four substances on this ph scale is slightly basic? a. Calcium hydroxide c. Whole milk b. Human blood d. Lemon juice file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 7/17

8 A ph of 7 is neutral less than 7 is an acid greater than 7 is a base We want the option that is slightly greater than 7 A 22. Which element will most likely form covalent bonds with fluorine? a. Carbon c. Neon b. Potassium d. Tin Covalent bonds are between 2 nonmetals (ionic would have a metal and nonmetal) Fluorine is a nonmetal so we need another nonmetal carbon is a nonmetal yes potassium is a metal no neon is a nonmetal, but it is also a noble gas. Therefore it is extremely stable and does not react to make compounds no tin is a metal no D 23. The physical process of evaporation involves a. ion formation c. transferring valence electrons b. electron sharing d. overcoming intermolecular forces C 24. B 25. For something to evaporate, the molecules have to have enough energy to get away from each other and overcome any attraction they have with each other. inter means between so intermolecular forces are the forces between the molecules. This is what needs to be broken. C 2 H 4 + _?_O 2 CO 2 + H 2 O How many moles of O 2 are in the chemical equation when balanced using the lowest whole numbers? a. 5 b. 4 c. 3 d. 2 When the equation is balanced, we would have the coefficients (and therefore relative moles) of: _1_ C 2 H 4 + _3_O 2 _2_CO 2 + _2_ H 2 O file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 8/17

9 While English physicist J.J. Thomson was carrying out experiments on cathode rays, he was able to determine that the rays consisted of particles he classed corpuscles. These particles were later namesa. protons c. gamma rays b. electrons d. neutrons J.J. Thomson discovered the electron using the cathode ray experiment; plus the diagram shows the particle leaving the negative side and being attracted to the positive anode. Since electrons a negative, it can be concluded that the particle is the electron. D 26. In the Haber process, nitrogen (N 2 ) and hydrogen (H 2 ) are directly combined to form ammonia (NH 3 ). Which illustration contains the stoichiometric quantities of the reactants for this reaction? a. c. file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 9/17

10 b. d. For every N, we need 3 H (NH 3 ). The illustration that shows this ratio is because 4:12 reduces to 1:3 C 27. A beaker of water is placed in a large sealed jar that is attached to a vacuum pump. As air is pumped out of the jar, the water begins to boil because a. the temperature of the water decreases as the surrounding pressure decreases b. the lower pressure inside the jar causes the water to contract c. the air pressure in the jar has been lowered until it is equal to the vapor pressure of the water d. the pressure on the water is insufficient to hold the hydrogen and oxygen atoms together, resulting in a decomposition reaction file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 10/17

11 To evaporate, the water molecules have to be able to get away from each other. However, at normal pressure, the water molecules that try to leave run into air molecules that knock them back into the liquid in the beaker. As the pump removes the air molecules, the water molecules can start to escape. So, choice c is the option that describes this the best. B 28. How many moles are in 2.04 x molecules of H 2 O? a mol c x mol b mol d x mol uses Avogadro s Number: 2.04 x molecules x = D 29. What is the name for FeCl 3 using the IUPAC nomenclature rules? a. Iron chloride c. Iron trichloride b. Iron (II) chloride d. Iron (III) chloride IUPAC stands for The International Union of Pure and Applied Chemistry and is the current way for naming compounds. In this case, you would have to realize that Fe is a metal, therefore you have an ionic compound. Ionic compounds don t use prefixes so Iron trichloride is out as a choice. Next, we have to see that iron is a transition element (metal) with more than one oxidation number, so a roman numeral is needed (eliminates Iron chloride). Since the oxidation of the Fe in this compound is +3 (+3x1Fe = 1x3Cl), the roman numeral needs to be a 3 to match this charge. C 30. Which of these correctly describes how organic catalysts operate in biological reactions? a. They are used up in the reactions. b. They lower the overall energy of the reactions. c. They lower the activation energy of the reactions. d. They keep the temperature of the reactions constant. Catalyst speed up the reaction by lowering the activation energy. A 31. What volume will 35.9 g of hydrogen gas (H 2 ) occupy at STP? a. 399 L c. 804 L b. 798 L d. 1,620 L STP means standard temperature and pressure, which means you can use 22.4 file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 11/17

12 L/mol In this problem, we are going to have to change the grams of H 2 to moles using the molar mass of H 2 and then change those moles to L using the Note: they used the entire atomic mass of H to get the answer. If you used 1.0 for hydrogen and got an answer of 402, you would have to notice that 399L is the closest answer and the difference is the rounding. 35.9g x x = B 32. H > x2= Ca(NO 3 ) 2 + _?_H 3 PO 4 Ca 3 (PO 4 ) 2 + HNO 3 When this equation is balanced, the coefficient in front of H 3 PO 4 is a. 1 b. 2 c. 3 d. 4 When the equation is balanced, we would have the coefficients of: _3_ Ca(NO 3 ) 2 + _2_H 3 PO 4 _1_Ca 3 (PO 4 ) 2 + _6_ HNO 3 D 33. Increasing the volume of a sealed container will cause the gas particles within the container to a. form a liquid c. increase in molecular attraction b. collide more frequently d. exhibit lower pressure D 34. By increasing the volume, you are giving the molecules more room, therefore: form a liquid incorrect, you would have to force the gas particles together to make them turn into a liquid collide more frequently incorrect, you gave them more room so they will collide less frequently increase in molecular attraction incorrect, you gave them more space so they will have less opportunity to be attracted to each other exhibit lower pressure correct, and this follows Boyle s law, as volume increases, pressure decreases Melting Point Results ( C) Trial Group 1 Group 2 Group 3 Group Each of four groups of students determine and recorded the melting point of a solid compound. If the actual melting point is 113 C, which group has the best precision? file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 12/17

13 a. Group 1 c. Group 3 b. Group 2 d. Group 4 Precision is how close your numbers are to each other, so the 113 C is irrelevant to this problem. (It would only be used for accuracy; how close the group is to the correct answer). Plus, make sure you are reading down the columns for each group. But the group with the most consistent (or precise) numbers is Group 4 with 110, 111, 111, and 110. A 35. Consider any set of three elements in the same period on the periodic table. For which characteristics is the average for the three elements always equal to the value of the middle element? a. Atomic number c. Number of neutrons b. Atomic mass d. Number of isotopes Since atomic number always increases by 1 as you increase elements, this is the only characteristic that is listed that is consistent enough to have the average work. B 36. A substance has a molecular formula of C 8 H 10 N 4 O 2. The empirical formula is a. C 2 H 6 N 2 O c. C 9 H 7 N 3 O b. C 4 H 5 N 2 O d. CHNO The empirical formula is the simplified ratio of all the atoms in a compound. Since all the numbers in the molecular formula can be divided by 2, it would become C 4 H 5 N 2 O. D 37. What is the name for the compound AlI 3? a. Aluminum (I) iodide c. Aluminum (III) iodide b. Aluminum triiodide d. Aluminum iodide In this case, you would have to realize that Al is a metal, therefore you have an ionic compound. Ionic compounds don t use prefixes so Aluminum triiodide is out as a choice. Next, we have to see that aluminum is a metal with only one oxidation number (+3), so a roman numeral is NOT needed (eliminates Aluminum (I) iodide and Aluminum (III) iodide). B 38. 2C 4 H O 2 8CO H 2 O How many moles of carbon dioxide (CO 2 ) are produced when reacting 6.00 moles of butane (C 4 H 10 ) in excess oxygen (O 2 )? a mol c mol b mol d. 1,060 mol file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 13/17

14 Excess oxygen means we have extra O 2 and therefore do not need to worry about it in this problem. So, we need to change moles of C 4 H 10 to moles of CO 2. In class we talked about how to recognize how many steps you will need in your stoichiometry problem. Since they gave us moles and asked for moles, we don t need the first or last step. We only need the step to switch the compounds (mole ratio step using the coefficients in the balanced equation) 6.00 mol C 4 H 10 x = 24.0 mol CO 2 The other way to think of this problem is that coefficients equal relative moles. So, if we are tripling the number of moles of butane (2 >6), then we have to triple the amount of carbon dioxide (8x3=24) A 39. Which structure represents a nonpolar molecule? a. c. b. d. To be nonpolar, the molecule has to be symmetrical. The only symmetrical molecule is a. b is not symmetrical due to the alcohol group (OH) being different from the rest of the Hs c is not symmetrical due to the Cl being different from the Hs file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 14/17

15 d is not symmetrical due to the O being different from the Hs C 40. Using only one trial to collect data in an experiment a. makes it easier to determine a valid conclusion b. reduces the percent error in the results c. causes the conclusion to be less reliable d. requires data with more significant figures Only having one trial is NOT advised because one cannot compare the results to see if any sources of error occurred during the trial. As a result, the data and the results cannot be truly trusted, thus making the conclusion less reliable. B 41. A common product of acid base neutralization reactions is a. hydrogen c. carbon dioxide b. water d. oxygen During a neutralization reaction, an acid (tends to start with H) and a base (tends to end with OH) react to form water (results from the H and OH coming together) and a salt. D 42. Data Table Solution Brightness of Light ph Bulb NaHCO 3 Bright 8.4 HClO Dim 3.7 NaNO 3 Bright 7.0 CH 3 NH 2 Dim 8.0 Based on the information provided, which solution is a base and a weak electrolyte? a. NaHCO 3 c. NaNO 3 b. HClO d. CH 3 NH 2 A weak electrolyte would make the light bulb glow dimly (strong electrolytes would make it bright). A base has a ph greater than 7. So we need to look for something that is dim and a ph>7. file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 15/17

16 B 43. A 44. What is the half life of Americium 242? a. 11 hours c. 32 hours b. 16 hours d. 64 hours A half life is the amount of time required to lose half of your material. According to the graph, it takes 16 hours to go from 80 to 40. Two electrons are shared equally in bromine (Br 2 ). What type of bond is represented between the bromine atoms in this Lewis structure? a. Nonpolar covalent bond c. Metallic bond b. Polar covalent bond d. Ionic bond Since Br is a nonmetal and we have a compound between two nonmetals, we have a covalent bond. (Ionic would be between a metal and nonmetal and metal is between two metals). And because the electrons are being shared equally, it would be a nonpolar covalent bond. A 45. A student is studying the effects of several solutions on the prevention of the browning of apples. The student used solutions having different ph values and immersed three apple slices in equal volumes of the solutions. Which of these is the independent variable in this investigation? a. ph of solution c. Number of apple slices b. Shade of brown d. Volume of solutions file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 16/17

17 The Independent variable is what the scientist changes (put yourself in the position of the scientist and ask what did I change). In this case, I changed the ph of the solution. Other part of the experiment review: (The dependent variable is what changes because of the independent variable. In this case the shade of the apple changes because of the ph of the solution. Constants stay the same throughout the experiment; the number of apples and volume of solution are constants. And a control is what we can set up to compare our results to and is usually lacking the independent variable. In this case, if we had an apple not in a solution or maybe a ph of 7 (neutral); that would most likely be our control). D 46. An experiment produced 0.10 g CO 2 with a volume of L at STP. If the accepted density of CO 2 at STP is 1.96 g/l, what is the approximate percent error? a. 110% c. 71% b. 92% d. 8.2% First, we need to determine the experimental density by solving D=m/V. D = 0.10g/0.056L = 1.8 g/l Then, we need to calculate % error by solving (acceptedexperimental)/accepted x 100 x100 = 8.2% file:///f:/sol%20review%20topics/chemistry%202010%20sol/2010_released_sol.htm 17/17