1. Chemistry practice questions

4. When copper and oxygen chemically unite, they form — F an ion G a gas H a compound J a mixture

5. When copper and oxygen chemically unite, they form — H a compound

6. Which of the following would most increase the rate at which magnesium nitrate dissolves in a liquid solvent? F Increasing the pressure on the liquid G Keeping the liquid still and undisturbed H Lowering the temperature of the liquid J Breaking the crystals into smaller pieces

7. Which of the following would most increase the rate at which magnesium nitrate dissolves in a liquid solvent? J Breaking the crystals into smaller pieces

8. Two students added a piece of zinc to a solution of hydrochloric acid in an open beaker. The mass of the products was found to be less than the total mass of the reactants. How should the students have conducted their experiment to reflect the law of conservation of mass? A the students should have used a less reactive metal in their experiment. B The students should have conducted the experiment in a closed system. C The students should have left the beaker on the scale during the entire reaction. D The law of conservation of mass does not apply to all chemical reactions, and the students’ results properly reflect that.

9. Two students added a piece of zinc to a solution of hydrochloric acid in an open beaker. The mass of the products was found to be less than the total mass of the reactants. How should the students have conducted their experiment to reflect the law of conservation of mass?. B The students should have conducted the experiment in a closed system.

10. Two students added a piece of zinc to a solution of hydrochloric acid in an open beaker. The mass of the products was found to be less than the total mass of the reactants. Which of the following statements best explains the loss of mass? A Zinc metal is more dense than the acid. B The chemical activity of the acid destroyed metal atoms. C A gas was released during the reaction. D Some of the zinc atoms failed to react.

11. Two students added a piece of zinc to a solution of hydrochloric acid in an open beaker. The mass of the products was found to be less than the total mass of the reactants. Which of the following statements best explains the loss of mass? C A gas was released during the reaction.

14. __Fe + __O 2 → __Fe 2 O 3 Iron reacts with oxygen in the air to form iron oxide. The unbalanced equation for this reaction is shown above. What are the coefficients when this equation is balanced? F 2,2,1 G 2,3,1 H 4,3,2 J 4,2,2

15. __Fe + __O 2 → __Fe 2 O 3 Iron reacts with oxygen in the air to form iron oxide. The unbalanced equation for this reaction is shown above. What are the coefficients when this equation is balanced? H 4,3,2

16. An inventor claims to have created a wind turbine that can convert 1 kilogram of water into 1 kilogram of oxygen and 1 kilogram of high-energy hydrogen fuel. 1 kg water → 1 kg oxygen + 1 kg hydrogen This claim is false because it — F violates the principle of constant composition G contradicts the law of conservation of matter H ignores the strength of the theory of strings J violates the rules of gravitational attraction

17. An inventor claims to have created a wind turbine that can convert 1 kilogram of water into 1 kilogram of oxygen and 1 kilogram of high-energy hydrogen fuel. 1 kg water → 1 kg oxygen + 1 kg hydrogen This claim is false because it — G contradicts the law of conservation of matter

18. Which of these steps in the digestive process is a physical change? F Water being absorbed in the large intestine G Enzymes breaking down proteins into amino acids H Saliva changing starches into sugars J Insulin breaking down simple sugars into smaller molecules

19. Which of these steps in the digestive process is a physical change? F Water being absorbed in the large intestine

20. Which characteristic of water molecules makes water a good solvent? F Mass G Polarity H Potential energy J Chemical energy

21. Which characteristic of water molecules makes water a good solvent? G Polarity

34. A student creates the above model of an atom. The overall charge of the atom represented in this model is B. Neutral

36. Beryllium Be

37. - - - - - - - - - +++++ ++++++ 00000

38. Sodium (Na) - - - - - - - - - +++++ ++++++ 00000

39. Which of the following conclusions can be drawn from the information shown? A.Most types of matter heat up at the same rate. B.Most types of matter cool down at the same rate. C.It takes less energy to heat 1 g of silver then 1 g of gold. D.It takes more energy to heat 1 g of water then 1 g of copper. Substance Specific heat capacity (J/kg x C) Specific heat capacity (J/kg x o C) Aluminum899 Copper387 Gold129 Silver234 Water4,184 Wood176

40. Which of the following conclusions can be drawn from the information shown? A.It takes more energy to heat 1 g of water then 1 g of copper. Substance Specific heat capacity (J/kg x C) Specific heat capacity (J/kg x o C) Aluminum899 Copper387 Gold129 Silver234 Water4,184 Wood176

41. Which of the following elements would be the best conductor? A. Au B. C C. Ne D. S

42. Which of the following elements would be the best conductor? A. Au

43. Which two elements are most similar? F. H and O G. Fe and Co H. Li and F J. Mg and Sr

44. Which two elements are most similar? J. Mg and Sr

45. The formula that represents sodium chloride, commonly known as salt, is – A.H 2 O B.NaCl C.SaLt D.SoCh

46. The formula that represents sodium chloride, commonly known as salt, is – B. NaCl

47. This Bohr model represents the element – F. Carbon G. Fluorine H. Oxygen J. Neon

48. This Bohr model represents the element – G. Fluorine

49. What part of the oxygen atom contains neutral particles? A.Electrons B.Electron clouds C.Isotopes D.Nucleus

50. What part of the oxygen atom contains neutral particles? D. Nucleus

51. Which of the following must be the same for every atom of the element hydrogen? F. Atomic mass G. Number of electrons H. Number of neutrons J. Number of protons TAKS 3 TEKS 8.8A, 8.8B

52. Which of the following must be the same for every atom of the element hydrogen? J. Number of protons TAKS 3 TEKS 8.8A, 8.8B

53. You find an object that is shiny and solid. It conducts heat and electricity. How would the object be classified? A.noble gas B.non-metal C.metal D.halogen TAKS 3 TEKS 8.9B

54. You find an object that is shiny and solid. It conducts heat and electricity. How would the object be classified? C. Metal TAKS 3 TEKS 8.9B

55. Which of the following is not a property of an atom? F. Color G. Electric charge H. Mass J. Number of protons TAKS 3 TEKS 8.8A, 8.8B

56. Which of the following is not a property of an atom? F.Color

57. Which of the following changes is not a physical change? A.Beating an egg B.Making a tossed salad C.Boiling water D.Frying an egg

58. Which of the following changes is not a physical change? D. Frying an egg

59. Which of the following would be a poor conductor of heat? a.F b.Ca c.Au d.Fe

60. Which of the following would be a poor conductor of heat? a.F

61. Which of the following is a naturally occurring chemical a.Salt b.Nylon c.Plastic d.Tylenol

62. Which of the following is a naturally occurring chemical a.Salt

63. According to the Periodic Table of the Elements, which element is most similar to magnesium (Mg)? A calcium (Ca) B iodine (I) C sodium (Na) D sulfur (S)

64. According to the Periodic Table of the Elements, which element is most similar to magnesium (Mg)? A calcium (Ca)

65. When Chemical X is added to a certain liquid, the chemical breaks into Substances Y and Z. It is not possible to break Substances Y and Z into simpler particles. Which statement is best supported by this evidence? A Chemical X is an element. B Chemical X is soluble in water. C Substances Y and Z are elements. D Substances Y and Z are compounds.

66. When Chemical X is added to a certain liquid, the chemical breaks into Substances Y and Z. It is not possible to break Substances Y and Z into simpler particles. Which statement is best supported by this evidence? C Substances Y and Z are elements.

67. The graph shows the relationship between mass and time for a radioactive element during radioactive decay. What is the half-life (time it takes for half of the element) to break down? A.20 billion years B.60 billion years C.125 billion years D.180 billion years

68. The graph shows the relationship between mass and time for a radioactive element during radioactive decay. What is the half-life (time it takes for half of the element) to break down? A.60 billion years