2009 Chemistry Released SOL Test

Transcription

1 Name: Score: 50 / 50 points (100%) 2009 hemistry Released SOL Test Multiple hoice Identify the choice that best completes the statement or answers the question. D D 1. Which of these would be best to measure 12.6 ml of liquid ethanol? a. 25 ml beaker c. 25 ml Erlenmeyer flask b. 25 ml volumetric flask d. 25 ml graduated cylinder D Out of these, the graduated cylinder is the only piece of equipment with markings small enough to give an accurate reading. 2. Potassium (K) has a smaller atomic mass than argon (Ar) even though the atomic number of potassium is larger than the atomic number of argon. Which of the following best accounts for this observation? a. At STP, potassium is in the solid phase, but argon is a gas. b. It is easier for a potassium atom to lose an electron than it is for an argon atom. c. The most common isotopes of argon have more protons than the most common isotopes of potassium. d. The most common isotopes of potassium have fewer neutrons than the most common isotopes of argon. D Protons + Neutrons = Mass If you change the protons, you change the element If you change the neutrons, you change the isotope So, the number of protons is set, but the neutrons can be changed and therefore will affect the overall mass. A 3. Which of the following is the correct Lewis electron dot diagram for the sodium atom? a. c. file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 1/18

2 b. d. A Since sodium is in the first column, it gets one dot. Remember the most dots an element can get is A compound has a mass of x10 2 g/mol. The number of significant figures in this mass is a. 2 b. 4 c. 5 d. 7 All numbers before the x10 2 are significant, but the x10 2 is not counted toward significant figures A 5. What are the coefficients of the correctly balanced equation? a. 1, 3, 2, 3 b. 0, 2, 2, 3 c. 1, 2, 2, 2 d. 2, 6, 4, 3 A Makes 2 Fe s, 6 O s and 3 s on each side and is the only one that works A 6. The correct formula for dinitrogen pentoxide is a. N 2 O 5 b. N 5 O c. NO 5 d. N 2 O D A di = 2 penta = 5 So we need 2N and 5O or N 2 O 5 7. When ionic compounds are named, the name of a monatomic anion will end in which of the file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 2/18

3 following suffixes? a. ic b. ite c. ate d. ide D D elements end in ide ate and ite are for polyatomic anions (more than 1; not mono) and ic is used with acids 8. When 1 g of sodium chloride (Nal) is placed in 100 g of water, a solution results. Once the solution is prepared, water is now considered what part of the solution? a. Solid b. Liquid c. Solute d. Solvent D Solvents (water in this case) dissolve the solutes (Nal in this case) in a solution D 9. What is the name of the compound with the formula Pl 5? a. Phosphorus(I) chloride c. Phosphorus pentachlorate b. Phosphorus(V) chloride d. Phosphorus pentachloride D Does it have a metal? No So it is covalent. Is it just one element or does it start with an H? No so it is not a diatomic or acid. So it has to be a binary molecular covalent compound use the prefixes and name ends in ide B 10. How many electrons does the iron ion have when it forms the ionic compound Fel 3? a. 20 b. 23 c. 26 d. 29 B Switchy Switchy tells me the Iron has a +3 charge. + means it lost electrons, so 26 (atomic number) 3 = 23 A 11. ovalent bonds mainly occur between a. two nonmetallic elements b. two metallic elements file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 3/18

4 c. one metallic element and one nonmetallic element d. one metalloid and one metallic element A covalent involve two nonmetals All metals metallic Metal and nonmetal ionic Metallic and metalloid usually treated as ionic A 12. What is the volume of the water in this graduated cylinder? a ml b ml c ml d ml A It is between 4 and 5 so it will be 4.. Each small mark equals a tenth and since it hasn t reached the 4th line, the best answer is B 13. If substance X is a liquid, substance Y is a gas, and substance Z is a solid, and all are at the same temperature and pressure, then the order of increasing strength of their intermolecular forces would be a. X < Y < Z b. Y < X < Z c. Z < Y < X d. Y < Z < X B Solids have the strongest bonds holding them together (hence why they are solids, tightly packed, definite shape and volume), gases have the least (that is why they are bouncing around by themselves). file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 4/18

5 Therefore, it would go solid, liquid, gas. Looking at the < (less than) and > (greater than), it would have to be Y (the gas) is less than X (the liquid) which is less than Z (the solid) 14. If a sample has a mass of 1.25 x 10 2 g and a volume of 51 ml, what is its density? a g/ml b g/ml c. 2.5 g/ml d. 250 g/ml D = m/v 1.25x10 2 / 51 = 2.45 or 2.5 B 15. What is the empirical formula of the compound with the molecular formula 6 H 12? a. H b. H 2 c. H 4 d. 2 H 6 B Need to simplify the 6 and 12. Since both can be divided by 6, they would go to 1 and 2. B 16. The diagram shows water molecules in an open beaker and water molecules that have evaporated into the air above the beaker. Which change in this system will increase the rate of evaporation? a. Adding salt to the water b. Increasing the temperature of the water c. Increasing the pressure of the air above the water d. Increasing the humidity of the air above the water file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 5/18

6 B Heating water makes it evaporate faster Adding salt makes it boil at a higher temperature Increasing the pressure would force the water from the air back into the beaker Increasing the humidity means there are more molecules in the air, increasing the chance that our water molecules would bounce back into the beaker. B 17. A chemist is examining an unidentified element sample with oxidation states of +2, +3, and +6. The element has a shielding effect similar to that of potassium (K). Which statement about the unidentified element is most likely true? a. It has the same number of neutrons as potassium. b. It is a transition metal from the same period as potassium. c. It is one of the heaviest elements in potassium s group. d. It is a mix of three unstable isotopes of potassium. B Shielding effect stays the same as you go left and right on the periodic table so it is in the same row as K and the fact that it has more than one oxidation number tells us that it is in the middle of the periodic table (transition element) Potassium only has a oxidation of +1 (column one) so it is not potassium so It is a mix of three unstable isotopes of potassium. is out Neutrons do not affect oxidation states, only electron do so It has the same number of neutrons as potassium. is out Groups go up and down and the shielding effect increases as you go down the group so It is one of the heaviest elements in potassium s group. is out 18. The reaction for the decomposition of ammonia (NH3 ) can be written as shown. If a student starts with 21.7 g of NH 3, how many grams of hydrogen (H 2 ) gas will be produced by the reaction? a g b g c g d g Stoichiometry file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 6/18

7 21.7 g NH 3 x = 1.28 mol NH 3 x = 1.92 mol H 2 x =3.84g ~ 3.85 g N 14 H 1x The product in a balanced reaction is 4Al 2 O 3. Which of the following shows the number of aluminum and oxygen atoms in 4Al 2 O 3? a. 8 atoms of aluminum and 3 atoms of oxygen b. 6 atoms of aluminum and 3 atoms of oxygen c. 8 atoms of aluminum and 12 atoms of oxygen d. 6 atoms of aluminum and 7 atoms of oxygen Distribute and multiply the 4. So 4x2=8 Al, and 4x3=12 O B 20. According to the ph scale, which substance is lightly acidic? a. Battery acid c. Baking soda b. Black coffee d. Drain cleaner B Acids are between 0 7, with 7 being neutral. The closest thing to 7 on the acid side is black coffee D 21. Which of these is most likely to form between elements transferring electrons to form oppositely charged particles? a. A metallic bond c. A covalent bond b. A hydrogen bond d. An ionic bond file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 7/18

8 D Ionics result from a transfer of electrons and the ions attracted each other after the transfer has occurred. 22. Which of the following is a chemical change? a. Salt is dissolved in water. b. Water is boiled on a stove. c. Gasoline combusts in an engine. d. opper metal is stretched into a long wire. ombustion is chemical since it makes two new compounds (O 2 and H 2 O) from the gasoline and these compounds have new properties. Making solutions and phase changes are both physical so Salt is dissolved in water. and Water is boiled on a stove. are out as well as stretching. B 23. The table shows the specific heat capacity of four substances. For an equal mass of each substance, which one will require the least amount of heat to raise its temperature from 20 o to 30 o? a. Aluminum c. arbon dioxide b. Glass d. Water B The lower the heat capacity, the less heat it will take. Since glass has the lowest, it will take the least amount of heat. 24. What is the volume occupied by 51.0 g of ammonia (NH 3 ) gas at STP? a L b L c L d L file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 8/18

9 51g NH 3 x =3 mol x =67.2 N 14 H 1x3 17 B 25. Which substance will release the greatest amount of heat when 1.00 mol is frozen? a. Argon b. Benzene c. Mercury d. Water B The higher the H fus, the higher the amount of heat released. D 26. A student hypothesizes that bromine (Br) has different chemical properties from krypton (Kr). The periodic table supports this hypothesis by indicating that a. bromine is a metal while krypton is a nonmetal b. one mole of bromine is heavier than one mole of krypton c. bromine and krypton are members of the same family d. bromine and krypton have different numbers of valence electrons D Both are nonmetals (far right of periodic table, arrows at bottom of table confirm this) Krypton is heavier (Kr = 83.80; Br = ) Not in the same column so not in the same family But the do have different number of valence electrons (dots in Lewis Structure; Br has 7; Kr has 8) file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 9/18

10 B 27. A mixture of gases with a pressure of 800 mm Hg contains 10% oxygen and 90% nitrogen by volume. What is the partial pressure of the oxygen gas in the mixture? a. 10 mm Hg b. 80 mm Hg c. 700 mm Hg d. 800 mm Hg B 10% of 800 mmhg (unit of pressure) is 80 D 28. One example of an ionic compound is a. F 2 b. O 2 c. HBr d. Mgl 2 D To be ionic, it must have a metal and a nonmetal and Mg is the only metal mentioned, everything else is a nonmetal 29. Le hatelier s principle describes what happens to a system in equilibrium when a stress occurs. All of the following could shift an equilibrium EXEPT a. changing the pressure on the system b. changing the temperature of the system c. changing the identity of the catalyst d. changing the concentration of one of the components atalyst affect the rate of a reaction, not the amounts on each side. Remember this is talking about the seesaw so temp and concentration definitely affect the seesaw. Pressure is the thing that we have to look at the coefficients instead of the seesaw. The catalyst would be like adding something that doesn t appear on either side. 30. What type of reaction is shown? a. Precipitation c. Single replacement b. Neutralization d. Double replacement Single Replacement element + compound goes to element + compound where the element switches places with something from the compound. file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 10/18

11 A 31. Which graph best shows the relationship between the volume of a gas and its temperature as the gas pressure remains constant? a. F c. H b. G d. J A The relationship between volume and temperature is direct as one goes up, the other goes up; as one goes down, the other goes down. F is the choice that shows this relationship. B 32. Hydrogen chloride is a covalent compound. which is a correct Lewis dot structure for Hl? a. c. b. d. B l wants 8 dots, H only wants 2 file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 11/18

12 B 33. Which is the best use for a fume hood? a. Storing glassware c. overing volatile compounds b. Removing toxic vapors d. Mixing chemicals that release O 2 B The fume hood is the device in the back of the room that has the exhaust fan that turns on when you flip on its light. It is designed to remove fumes that are formed during a reaction. D 34. Which of the following equations is balanced? a. Na + 2l 2Nal 2 c. Na + l 2 2Nal b. 2Na + l 2 2Nal 2 d. 2Na + l 2 2Nal D Na + 2l 2Nal 2 Not enough l s (2 to 4) 2Na + l 2 2Nal 2 Not enough l s (2 to 4) Na + l 2 2Nal Too many Na s (1 to 2) 2Na + l 2 2Nal Just Right (2 Na s and 2 l s) D 35. A bottle of chemical Q spills on the floor. According to the MSDS, what is the proper file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 12/18

13 response to this accident? a. Letting the chemical evaporate by blowing fans on the spill. b. Diluting the chemical with water, absorbing the liquid with inert material, and disposing of it in the trash. c. Wiping up the chemical using paper towels and disposing of them in the trash. d. Absorbing the chemical with inert material and disposing of it in a chemical waste container. D To solve this, we must look at the accidental spill instructions 36. The specific heat of aluminum is How much heat is required to raise the temperature of a 30.0 g block of aluminum from 25.0 o to 75.0 o? a J b J c J d J q=mc p T, so q = (30)(0.900)(50) = 1350 Another way to think about it if you don t have the formula We want our answers is J (since all choices end in J), we have a unit that is in. If we multiply this unit by grams and, they would cancel out these units and give us our answer in J. {g x ( ) x } 37. When an electric current is passed through water, the reaction shown takes place. If the arrow were pointing in the opposite direction, what type of reaction would the new reaction represent? a. Single replacement c. Synthesis b. Double replacement d. Decomposition Two combine into 1, that is a synthesis or combination reaction Decomp is when they break down Single is element + compound > element + compound with some switching file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 13/18

14 Double is compound + compound > compound + compound with some switching D 38. The picture shows a small section of elements from the periodic table. Which element has one more proton than element X? a. 1 b. 2 c. 3 d. 4 D Atomic numbers increase as you go across the periodic table and atomic number equals the number of protons. Therefore, 4 is in the spot that would be the next highest atomic number on the periodic table and would have one more proton. 39. If 1.0 mole of methane reacts with oxygen to produce carbon dioxide and water, what mass of water is produced? a. 16 grams b. 18 grams c. 36 grams d. 44 grams 1 mol x = 2 mol x = 36 grams H 1x2 = 2 O 16x1=16 18 D 40. An example of a chemical property is a. mass of a substance per unit volume c. point where solid becomes liquid b. ability to dissolve in solution d. tendency to undergo oxidation D change phases is a physical change point where solid becomes liquid is out file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 14/18

15 making solutions is a physical change ability to dissolve in solution is out measuring something s mass and volume is physical mass of a substance per unit volume is out oxidation is chemical since the oxidized substance is chemically changed (electrons are changed) tendency to undergo oxidation is the answer A 41. Students want to separate and compare the components of black ink and green ink. which technique is the best for the students to use? a. hromatography c. Filtration b. Decanting d. Evaporation A hromatography separates phases using a mobile and a stationary phase. We conducted this experiment where the mobile phase was water and the stationary phase was chromatography paper. The inks separated as the water rose up the paper. Decanting pouring a liquid, leaving the solid behind Filtration using filter paper to separate a solid from a liquid Evaporation Heating a liquid so it evaporates and leaves the solid behind 42. When 80 g of sodium hydroxide, NaOH, are dissolved in enough water to make 500 ml of solution, the molarity of the solution is a. 1 M b. 2 M c. 4 M d. 8 M Molarity (M) = mol/l 80g x = 2 mol M = 2 mol/0.500l = 4 M O 16 H 1 40 Na ml x =0.500 A 43. What is the name for the compound aso 4? a. alcium sulfate c. alcium sulfur oxide b. alcium sulfide d. alcium sulfur oxygen file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 15/18

16 A We have three different elements, so most likely we are dealing with an ionic compound with a polyatomic ion. Let us check, a is a metal, which leaves SO 4 as a polyatomic. a only has one oxidation number on the periodic table (+2) so no roman numeral is needed. As a result, we need to name the metal, then name the polyatomic ion. a is calcium and polyatomics end in ate or ite. Luckily, we only have one choice. D 44. If the ph of a solution is 4, what is the poh? a. 0 b. 6 c. 7 d. 10 D ph + poh = 14, so 14 4 = A student attempts to measure the specific heat capacity of an unknown liquid through repeated trials. She measures its specific heat capacity, in as 2.14, 2.11, 2.14, 2.12, and The specific heat capacity of the liquid should be recorded as a. 2 c b. 2.1 d We need to average the numbers and look at the sig figs. So ( )/5 = Now we have to worry about significant figures, since we are adding, we need to look at the decimal place. Since they all go to the hundredth spot, our answer should go to the hundredth spot. We do not need to worry about the five since it is an exact number. file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 16/18

17 B 46. If the temperature changes from point M to point N, at constant pressure, compound X undergoes a. one phase change c. three phase changes b. two phase changes d. no change in phase B It goes from a solid to a liquid, then from a liquid to a gas 2 phase changes 47. Which of these best describes the basis on which new scientific ideas are accepted or rejected? a. Popular support c. ompelling evidence b. Historical support d. Moral and ethical beliefs You have to have evidence that supports your hypothesis to either accept or reject it. Just because something is popular doesn t mean its right, history can also be wrong (the Earth is flat and is the center of the universe), and our beliefs sometimes differ from science. B 48. Based on its position in the periodic table, the element sulfur would be expected to have how many valence electrons? a. 4 b. 6 c. 8 d. 16 B file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 17/18

18 It is in column 16 (remember if you ignore the 1 it tells you the # of dots or the valence electrons) B 49. The number of molecules in 48.0 grams of oxygen gas (O 2 ) is a x c x b x d x B 48 g x = 1.5 mol x =9.03x A student determined that the density of a sample of tin is 8.00 g/ml, when the actual density of tin is 7.28 g/ml. What was the percent error in the student s calculation? a. 0.72% c. 9.9% b. 9.0% d. 91% (T E)/T x 100 (7.28 8)/7.28 x 100 = 9.89 % so the absolute value is 9.9 % file:///f:/sol%20review%20topics/hemistry%202009/2009_chemistry_released_sol_test.htm 18/18