Mansfield High School Chemistry EOC Benchmark-March 2013

Transcription

1 Mansfield High School Chemistry EOC Benchmark-March During an investigation a chemistry student makes the following observations about hydrogen gas: 1. It is gaseous at room temperature. 2. It is less dense than air. 3. It reacts explosively with oxygen. 4. It is colorless. 5. It is tasteless. The student is then asked to differentiate between the chemical and physical properties of hydrogen gas. Which of the above observations is a chemical property? A) 1 B) 2 C) 3 D) 4 E) 5 2. Which of the following are examples of physical change? A) dew forms on a blade of grass B) a halloween light stick glows after shaking C) an egg solidifies during cooking D) a hydrogen balloon explodes when contacted with a flame E) None of the above are physical changes. 3. Which of the following represents a physical property? A) Sodium metal is extremely reactive with chlorine gas. B) Mercury is a silver liquid at room temperature. C) the tendency of aluminum to "rust" D) the flammability of butane fuel E) the unreactive nature of argon gas 4.

2 5. When comparing liquids to gases, A) Both have a definite shape and definite volume. B) Both have an indefinite shape and indefinite volume. C) Both have an indefinite shape, but gases have a definite volume. D) Both have an indefinite shape, but liquids have a definite volume. 6. Which of the following items would be classified as a pure substance? A) sea water B) sugar C) air D) lemonade E) milk 7. A student conducts an investigation and observes that a substance cannot be chemically broken down into simpler substances. This is because the substance is considered to be A) a homogeneous mixture. B) an element. C) a heterogeneous mixture. D) a compound. E) an electron. 8. Which of the following is a characteristic of the modern periodic table? A) A group is a horizontal row on the periodic table. B) A period is a column on the periodic table. C) The elements in each group have similar chemical properties. D) The B groups contain the representative elements. E) The A groups contain the transition elements. 9.

3 Which of the following represents the Lewis structure for Cl? A) B) C) D) E) 12. The compound MgCl 2 is named A) magnesium chlorine. B) magnesium dichloride. C) magnesium (II) chloride. D) magnesium chloride. E) dimagnesium chloride. 13. The name given to an aqueous solution of HCl is A) hydrogen chloride. B) hypochlorous acid. C) chloric acid. D) chlorous acid. E) hydrochloric acid.

4 14. What is the correct formula for iron (III) sulfide? A) Fe 2 S 2 B) Fe 2 S C) FeS D) FeS 2 E) Fe 2 S What is the formula of carbon tetraiodide? A) CI B) CI 4 C) C 4 I D) CI 3 E) C 2 I Which of the following is the correct Lewis Structure for phosphorus tribromide, PBr 3?

5 17. Which of the following is the correct Lewis structure for hydrogen cyanide, HCN? 18. Electricity is the movement of electrons from one atom to another. Which choice best explains why metals are such good conductors of electricity? A) The valence electrons further away from the nucleus in metals, compared to nonmetals, and can thus be removed easier. B) The valence electrons of one atom are loosely bonded to all the atoms surrounding it as well. This allows greater ease of movement. C) Metallic atoms have extra electrons, so they will gladly lose those in favor of becoming stable. D) Because metals are so smooth electrons can easily slide across the surface 19. What is the molecular geometry of the SF 2 molecule? A) Linear B) Trigonal planar C) Tetrahedral D) Bent E) Trigonal Pyramidal 20. One mole of particles of any substance contains how many particles? A) 10 6 B) 3 x C) 3 x D) 6.02 x E) 6.02 x 10-23

6 grams of copper(ii) sulfate, CuSO 4, contains CuSO 4 atoms. A) 4 B) 6.02 x C) 1.51 x D) 2.41 x E) 2.41 x Calculate the mass percent composition of lithium in Li3PO4. A) % B) % C) % D) % E) % What coefficient is placed in front of O 2 to complete the balancing of the following equation? C 5 H 8 +? O 2 5 CO H 2 O A) 1 B) 3 C) 5 D) 7 E) 9

7 25. According to the following balanced reaction, how many grams of NO are formed from 388 grams of NO2 if there is plenty of water present? 3 NO2(g) + H2O(l) 2 HNO3(aq) + NO(g) A) 253 grams NO B) 84.3 grams NO C) 5.50 grams NO D) 129 grams NO E) 1160 grams NO 26. Which of the following is an example of potential energy? A) chewing food B) water stored in a reservoir C) burning wood D) a fan blade turning E) riding an exercise bike 27. As water boils, the heat transfer through the water is best described as (A) convection (B) conduction (C) radiation (D) insulation (E) temperature 28.

8 29. What is the specific heat of a substance that absorbs 2.5 x 10 3 joules of heat when a sample of 524 g of the substance is heated from 10.0 o C to 70.0 o C? A) J/g o C B) J/g o C C) 7.95 x 10-5 J/g o C D) J/g o C 30. A g sample of an unknown substance is burned in a calorimeter. The temperature of the 50.0 ml water, in the calorimeter, increases by 3.20 o C. Calculate the amount of heat released by this reaction. c water = J/g* o C A) 2.63 J B) 6.70 x 10 2 J C) 660 J D) 2.6 J 31. What precipitate is most likely formed from a solution containing Ba+2, Na+1, OH-1, and CO3-2? A) NaOH B) BaCO3 C) Na2CO3 D) Ba(OH)2 32. Which of the following ionic compounds would be considered insoluble in water? A) sodium chromate B) calcium chromate C) ammonium chromate D) cesium chromate 33. What is the molarity of a solution that contains 17 g of NH 3 in 0.50 L of solution? A) 34 M B) 0.50 M C) 2.0 M D) M E) 1.0 M

9 34. When added to water, which of the following substances will create the strongest electrolytic solution? A) sucrose B) ethyl alcohol C) lead (II) chromate D) sodium cyanide 35. In order to increase the solubility of a gas in water, what action should be taken? A) raise the temperature B) stir the solution C) increase the amount of CO 2 D) increase the pressure 36.

10 6HBr (aq) + 2Al(OH) 3 (aq) Above is the incomplete reaction of hydrobromic acid and aluminum hydroxide. What products will complete and balance the reaction? A) 3H 2 O + AlBr 3 B) 2AlH 3 + 6BrOH C) 6AlH3 + 3BrOH 38. D) 6H 2 O + 2AlBr Calculate the ph of a solution with [OH - ] = 1 x 10-6 M. A) -8.0 B) -6.0 C) 6.0 D) 8.0 E) 1.0 x Which of the following acids will dissociate the least in water? A) HNO 3 B) HBr C) H 2 SO 4 D) HCN