59. “A mixture is the chemical bonding of two or more substances in any proportion.” Is this statement true or false? Explain. The statement is false because mixtures are a physical blend of substances, not a chemical bonding of substances.

60. Which of the following are the same and which are different? a substance and a pure substance a heterogeneous mixture and a solution a substance and a mixture a homogeneous mixture and a solution Same Different

61. Describe how a homogeneous mixture differs from a heterogeneous mixture Homogeneous mixtures contain a single phase. Heterogeneous mixtures can have many phases.

62. Seawater is composed of salt, sand, and water 62. Seawater is composed of salt, sand, and water. Is seawater a heterogeneous or homogeneous mixture? Explain. Heterogeneous; composition is not uniform

63. Use iced tea with and without ice cubes as examples to explain homogeneous and heterogeneous mixtures. If you allow all of the ice cubes to melt, what type of mixture remains? Ice tea with ice cubes is a heterogeneous mixture. Ice tea without ice cubes is a homogeneous mixture. When all ice cubes melt, the remaining mixture is homogeneous.

65. State definition of element. An element is a substance that cannot be broken down into simpler substances by physical or chemical means.

66. Correct the following statements: An element is a combination of two or more compounds When a small amount of sugar is completely dissolved in water, a heterogeneous solution is formed. A compound is combination of two or more elements When a small amount of sugar is completely dissolved in water, a homogeneous solution is formed.

67. Name the elements contained in the following compounds: Sodium chloride (NaCl) Ammonia (NH4) Ethanol (C2H6O) Bromine (Br2) Sodium and chloride Nitrogen and hydrogen Carbon, hydrogen, and oxygen Bromine

69. Is it possible to distinguish between an element and a compound? Explain. Yes, elements can be distinguished from compounds. Compounds can be broken down into their component elements, whereas elements cannot be broken down into simpler substances.

70. How are the properties of a compound related to those of the elements that comprise it? The properties of a compound are unique to that compound and different from those of its component elements.

71. Which law states that a compound always contains the same elements in the same proportion by mass? The law of definite proportions.

72. a) What is the percent by mass of carbon in 44 g of carbon dioxide (CO2)? b) What is the percent mass of oxygen in 44 g of carbon dioxide (CO2)? (12 g/44 g) X 100% = 27% (32 g/44 g) X 100% = 73%

Simple Whole-Number Ratios of Elements 73. Complete the table by classifying the compounds as 1:1 or 2:2, 1:2 or 2:1, and 1:3 or 3:1. Compound Simple Whole-Number Ratios of Elements NaCl 1:1 CuO H2O 2:1 H2O2 2:2