Name: 1) Which species represents a chemical compound? 9114-1 - Page 1 NaHCO3 NH4 + Na N2 2) 3) 4) Which substance represents a compound? Co(s) O2(g) CO(g) C(s) Which terms are used to identify pure substances? an element and a mixture a solution and a compound Which particle diagram represents one pure substance, only? an element and a compound a solution and a mixture 5) Given the simple representations for atoms of two elements: Which particle diagram represents molecules of only one compound in the gaseous phase?
9114-1 - Page 2 6) Given the key: Which particle diagram represents a sample containing the compound CO(g)? 7) 8) 9) 10) 11) 12) 13) 14) 15) 16) 17) Which substance can be decomposed by a chemical change? Cu Cr CO Co Which substance can be decomposed by a chemical change? ammonia calcium potassium copper Which substance can not be decomposed by a chemical change? HF Ne H2O N2O A sample of unknown composition was tested in a laboratory. The sample could not be decomposed by physical or chemical means. On the basis of these results, the laboratory reported that the unknown sample was most likely an element a solution a compound a mixture Which substance can not be decomposed by ordinary chemical means? mercury methane ammonia ethanol Two different samples decompose when heated. Only one of the samples is soluble in water. Based on this information, these two samples are both the same element both the same compound two different compounds two different elements Two substances, A and Z, are to be identified. Substance A can not be broken down by a chemical change. Substance Z can be broken down by a chemical change. What can be concluded about these substances? Substance A is a compound and substance Z is an element. Both substances are elements. Both substances are compounds. Substance A is an element and substance Z is a compound. One similarity between all mixtures and compounds is that both consist of two or more substances combine in a definite ratio Which must be a mixture of substances? are homogeneous are heterogeneous solution liquid gas solid Which of these contains only one substance? rainwater sugar water Which of these terms refers to matter that could be heterogeneous? distilled water salt water mixture element solution compound
18) 19) 20) An aqueous solution of sodium chloride is best classified as a heterogeneous mixture heterogeneous compound homogeneous mixture homogeneous compound A sample is prepared by completely dissolving 10.0 grams of NaCl in 1.0 liter of H2O. Which classification best describes this sample? homogeneous compound heterogeneous mixture Given: homogeneous mixture heterogeneous compound 9114-1 - Page 3 Which diagram represents a mixture? 21) Given the diagrams X, Y, and Z below: 22) 23) 24) 25) 26) Which diagram or diagrams represent a mixture of elements A and B? X, only Z, only X and Z X and Y Which process would most effectively separate two liquids with different molecular polarities? conductivity fermentation distillation filtration A bottle of rubbing alcohol contains both 2-propanol and water. These liquids can be separated by the process of distillation because the 2-propanol and water have combined chemically and retain their different boiling points have combined physically and retain their different boiling points have combined physically and have the same boiling point have combined chemically and have the same boiling point Which physical property makes it possible to separate the components of crude oil by means of distillation? boiling point conductivity The laboratory process of distillation does not involve liquids with the same boiling points changing a liquid to vapor solubility melting point liquids with different boiling points changing a vapor to liquid Recovering the salt from a mixture of salt and water could best be accomplished by density determination filtration evaporation paper chromatography
27) 28) When a mixture of water, sand, and salt is filtered, what passes through the filter paper? water, sand, and salt water and sand, only Which mixture can be separated by using the equipment shown below? water, only water and salt, only 9114-1 - Page 4 NaCl(aq) and C6H12O6(aq) CO2(aq) and C6H12O6(aq) NaCl(aq) and SiO2(s) CO2(aq) and NaCl(aq) 29) 30) 31) 32) 33) 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? The mixture is heterogeneous and cannot be separated by filtration. The mixture is heterogeneous and can be separated by filtration. The mixture is homogeneous and cannot be separated by filtration. The mixture is homogeneous and can be separated by filtration. Which statement describes a chemical property of iron? Iron combines with oxygen to form rust. Iron can be drawn into a wire. Iron conducts electricity and heat. Iron can be flattened into sheets. Which statement describes a chemical property that can be used to distinguish between compound A and compound B? A dissolves in water, and B does not dissolve in water. A has a high melting point, and B has a low melting point. A does not burn in air, and B does burn in air. A is a blue solid, and B is a white solid. Which statement describes a chemical property of oxygen? Oxygen has a melting point of 55 K. Oxygen gas can be compressed. Oxygen can combine with a metal to produce a compound. Oxygen gas is slightly soluble in water. An example of a physical property of an element is the element's ability to form a compound with chlorine react with an acid react with oxygen form an aqueous solution
34) Given the particle diagram below representing four molecules of a substance: 9114-1 - Page 5 Which of the following particle diagrams best represents this same substance after a physical change has taken place? 35) 36) 37) 38) 39) 40) 41) 42) Which process represents a chemical change? crystallization of sugar melting of ice Which set of procedures and observations indicates a chemical change? corrosion of copper evaporation of water Large crystals are crushed with a mortar and pestle and become powder. A solid is gently heated in a crucible and the solid slowly turns to liquid. A cool, shiny metal is added to water in a beaker and rapid bubbling occurs. Ethanol is added to an empty beaker and the ethanol eventually disappears. Which type of change must occur to form a compound? chemical phase nuclear physical Which of the following changes is exothermic? sublimation of iodine melting of iron Which physical changes are endothermic? melting and evaporating melting and freezing freezing of water vaporization of ethanol condensation and deposition condensation and sublimation Which form of energy is converted to thermal energy when propane burns in air? nuclear electrical chemical electromagnetic Which transfer of energy occurs when ice cubes are placed in water that has a temperature of 45C? Thermal energy is transferred from the ice to the water. Thermal energy is transferred from the water to the ice. Chemical energy is transferred from the water to the ice. Chemical energy is transferred from the ice to the water. Two samples of gold that have different temperatures are placed in contact with one another. Heat will flow spontaneously from a sample of gold at 60C to a sample of gold that has a temperature of 80C 50C 60C 70C
43) 44) 45) 46) 47) 48) As the temperature of a substance decreases, the average kinetic energy of its particles remains the same increases decreases At 1 atmosphere and 298 K, 1 mole of H2O() molecules and 1 mole of C2H5OH() molecules both have the same density average kinetic energy mass vapor pressure An increase in the average kinetic energy of a sample of copper atoms occurs with an increase in volume concentration temperature pressure Which change in the temperature of a 1-gram sample of water would cause the greatest increase in the average kinetic energy of its molecules? 50C to 60C 60C to 50C 10C to 1C 1C to 10C The average kinetic energy of water molecules is greatest in which of these samples? 100 g of water at 45C 100 g of water at 25C Which kelvin temperature is equivalent to -24C? 10 g of water at 55C 10 g of water at 35C 297 K 226 K 249 K 273 K 9114-1 - Page 6