Third Quarter Cumulative Review Questions. 1. Which factor distinguishes a metallic bond from an ionic bond or a covalent bond?

Transcription

1 Name: Thursday, March 27, 2008 Third Quarter Cumulative Review Questions 1. Which factor distinguishes a metallic bond from an ionic bond or a covalent bond? 1. the mobility of electrons 3. the equal sharing of electrons 2. the mobility of protons 4. the unequal sharing of electrons 2. A gram sample of naturally occurring boron contains grams of boron-10 (atomic mass = atomic mass units) and grams of boron-11 (atomic mass = atomic mass units). Which numerical setup can be used to determine the atomic mass of naturally occurring boron? 1. (0.1978)(10.01) + (0.8022)(11.01) 2. (0.8022)(10.01) + (0.1978)(11.01) Which atom contains exactly 15 protons? 1. phosphorus oxygen sulfur nitrogen What is the total number of electrons present in an atom of?

2 5. The number of atoms in a molecule of helium is The concept of an ideal gas is used to explain 1. the mass of a gas sample 3. why some gases are monatomic 2. the behavior of a gas sample 4. why some gases are diatomic 7. When metals form ions, they tend to do so by 1. losing electrons and forming positive ions 3. gaining electrons and forming positive ions 2. losing electrons and forming negative ions 4. gaining electrons and forming negative ions 8. What is the formula for sodium oxalate? 1. NaClO 3. Na C O Na O 4. NaC H O Which element forms an ion that is larger than its atom? 1. aluminum 3. magnesium 2. chlorine 4. sodium

3 10. Given the reaction: Ca + 2H2O Ca(OH) 2 + H2 What is the total number of moles of Ca needed to react completely with 4.0 moles of H2O? As the elements in Period 3 are considered from left to right, they tend to 1. lose electrons more readily and increase in metallic 3. gain electrons more readily and increase in metallic character character 2. lose electrons more readily and increase in 4. gain electrons more readily and increase in nonmetallic character nonmetallic character 12. What is the chemical formula for copper (II) hydroxide? 1. CuOH 3. Cu 2(OH) 2. CuOH 2 4. Cu(OH) How many moles of solute are contained in 200 milliliters of a 1 M solution? A mixture of crystals of salt and sugar is added to water and stirred until all solids have dissolved. Which statement best describes the resulting mixture? 1. The mixture is homogeneous and can be separated by 3. The mixture is heterogeneous and can be separated by filtration. filtration. 2. The mixture is homogeneous and cannot be separated 4. The mixture is heterogeneous and cannot be separated by filtration. by filtration.

4 15. Which substance has the same molecular and empirical formulas? 1. C6H 4 3. CH4 2. C2H 4 4. C6H12O When a lithium atom forms an Li ion, the lithium atom 1. gains a proton 3. loses a proton 2. gains an electron 4. loses an electron 17. Which substance has a definite shape, a crystalline structure, and a definite volume at STP? 1. F 3. Br Cl 4. I Which kind of energy is stored in a chemical bond? 1. potential energy 3. activation energy 2. kinetic energy 4. ionization energy 19. The temperature at which the solid and liquid phases of matter exist in equilibrium is called its 1. melting point 3. heat of fusion 2. boiling point 4. heat of vaporization

5 20. The temperature of a sample of a substance changes from 10 C to 20 C. By how many Kelvins does the temperature change? Base your answer to the question on the information below. An atom has an atomic number of 9, a mass number of 19, and an electron configuration of Figure 1 What is the total number of neutrons in this atom? Answer: neutrons 22. Given the reaction: CH 4 + 2O2 CO 2 + 2H2O What amount of oxygen is needed to completely react with 1 mole of CH 4? 1. 2 moles 3. 2 grams 2. 2 atoms 4. 2 molecules 23. An atom of carbon-14 contains 1. 8 protons, 6 neutrons and 6 electrons 3. 6 protons, 8 neutrons and 8 electrons 2. 6 protons, 6 neutrons and 8 electrons 4. 6 protons, 8 neutrons and 6 electrons

6 24. Which statement is true about the properties of the elements in any one period of the Periodic Table? 1. They are determined by the number of neutrons. 3. They change in a generally systematic manner. 2. They are determined by the number of electrons in the first 4. They change in a random, unpredictable shell. manner. 25. What is the total number of hydrogen atoms required to form one molecule of C H (OH)? Which electron-dot structure represents a non-polar molecule? Which substance is composed of atoms that all have the same atomic number? 1. magnesium 3. ethane 2. methane 4. ethene 28. Which statement is true about a proton and an electron? 1. They have the same masses and the same charges. 3. They have different masses and the same charges. 2. They have the same masses and different charges. 4. They have different masses and different charges.

7 29. Under which conditions does a real gas behave most like an ideal gas? 1. at low temperatures and high pressures 3. at high temperatures and high pressures 2. at low temperatures and low pressures 4. at high temperatures and low pressures 30. Which process is a chemical change? 1. melting of ice 3. subliming of ice 2. boiling of water 4. decomposing of water 31. Which Lewis electron-dot diagram properly shows a sulfur atom in the ground state? At STP, solid carbon can exist as graphite or as diamond. These two forms of carbon have 1. the same properties and the same crystal structures 3. different properties and the same crystal structures 2. the same properties and different crystal structures 4. different properties and different crystal structures 33. The temperature of 100 grams of water changes from 16 C to 20 C. What is the total number of joules of heat energy absorbed by the water? J J J J

8 34. The modern model of the atom is based on the work of 1. one scientist over a short period of time 3. many scientists over a short period of time 2. one scientist over a long period of time 4. many scientists over a long period of time What is the total number of electrons in a S ion? Which group contains elements that are monatomic gases at STP? Which nonmetal is a liquid at STP? 1. oxygen 3. chlorine 2. bromine 4. mercury 38. The compound CO 2(s) sublimes readily at 25 C. Which properties are usually associated with a compound that undergoes this kind of change? 1. high vapor pressure and high intermolecular 3. low vapor pressure and high intermolecular attractions attractions 2. high vapor pressure and low intermolecular attractions 4. low vapor pressure and low intermolecular attractions

9 39. In which sample are the particles arranged in a regular geometric pattern? 1. HCL(l) 3. N (g) 2 2. NaCl(aq) 4. I (s) Which sample of water has the lowest vapor pressure? ml at 50 C ml at 40 C ml at 30 C ml at 20 C 41. Based on the nature of the reactants in each of the equations below, which reaction at 25 C will occur at the fastest rate? 1. C(s) + O 2(g) CO 2 (g) 2. NaOH(aq) + HCl(aq) NaCl(aq) + H2O( ) 3. CH3OH( ) + CH3COOH( ) CH3COOCH 3 (aq) + H2O( ) 4. CaCO (s) CaO(s) + CO (g) What effect does the addition of a catalyst have on a chemical reaction at equilibrium? 1. It increases the rate of the forward reaction, 3. It increases the rate of both the forward and reverse only. reactions. 2. It increases the rate of the reverse reaction, 4. It decreases the rate of both the forward and reverse only. reactions. 43. Which statement best describes the production of a chlorine molecule according to the reaction Cl + Cl Cl kcal? 1. A bond is broken, and the reaction is exothermic. 3. A bond is formed, and the reaction is exothermic. 2. A bond is broken, and the reaction is endothermic. 4. A bond is formed, and the reaction is endothermic.

10 44. Given the balanced equation: 4Fe(s) + 3O (g) Which phrase best describes this reaction? 1. endothermic with H = kj 2. endothermic with H = kj 3. exothermic with H = kj 4. exothermic with H = kj Fe O (s) kj 45. Which reaction results in an increase in the entropy of a system? 1. H O(g) H O(l) H O(l) H O(s) H O(l) 2H (g) + O (g) H (g) + O (g) 2H O(l) Given the change of phase: CO 2(g) CO 2(s) As CO 2(g) changes to CO 2(s), the entropy of the system 1. decreases 2. increases 3. remains the same 47. What is the safest method for diluting concentrated sulfuric acid with water? 1. add the acid to the water quickly 3. add the acid to the water slowly while stirring 2. add the water to the acid quickly 4. add the water to the acid slowly while stirring

11 48. Which piece of laboratory equipment should be used to remove a heated crucible from a ringstand? Given the reaction: 4Na + O 2 2Na2O How many grams of oxygen are completely consumed in the production of 1.00 mole of Na2O? Which expression defines the molality (m) of a solution? 1. grams of solute/kg of solution 3. grams of solute/kg of solvent 2. moles of solute/kg of solution 4. moles of solute/kg of solvent

12 Answer Key for Third Quarter Cumulative Review Questions

13 Third Quarter Cumulative Review Questions