(b) Fertilizers help to increase agricultural production. chemical property physical property

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1 Score 1. [Chang7 1.P.011.] Do the following statements describe chemical or physical properties? (a) Oxygen gas supports combustion. chemical property physical property (b) Fertilizers help to increase agricultural production. chemical property physical property (c) Water boils below 100 C on top of a mountain. chemical property physical property (d) Lead is denser than aluminum. chemical property physical property (e) Sugar tastes sweet. chemical property physical property

2 2. [Chang7 1.P.015.] Classify each of the following substances as an element or a compound. (a) dry ice element compound (b) carbon dioxide gas element compound (c) water element compound (d) hydrogen element compound

3 3. [Chang7 1.P.022.] Mercury is the only metal that is a liquid at room temperature. Its density is 13.6 g/ml. How many grams of mercury will occupy a volume of 86.1 ml? g 4. [Chang7 1.P.023.] Convert the following temperatures to degrees Celsius. (a) 95 F, the temperature on a hot summer day C (b) 17 F, the temperature on a cold winter day (c) a 123 F fever C C (d) a furnace operating at 1943 F C 5. [Chang7 1.P.036.] Carry out the following operations as if they were calculations of experimental results, and express each answer in the correct units with the correct number of significant figures. (a) km 6.10 km (b) ( mg) - ( mg) mg (c) ( dm) + ( dm) dm

4 6. [Chang7 1.P.069.] The total volume of seawater is L. Assume that seawater contains 3.1% sodium chloride by mass and that its density is 1.03 g/ ml. Calculate the total mass of sodium chloride in kilograms and in tons. (1 ton = 2000 lb; 1 lb = g) kg tons 7. [Chang7 1.P.075.] Percent error is often expressed as the absolute value of the difference between the true value and the experimental value, divided by the true value. true value - experimental value percent error 100% = true value The vertical lines indicate absolute value. Calculate the percent error for the following measurements. (a) The density of alcohol (ethanol) is found to be g/ml. (True value is g/ml.) % error (b) The mass of gold in an earring is analyzed to be g. (True value is g.) % error

5 8. [Chang7 1.P.079.] Chalcopyrite, the principal ore of copper (Cu), contains 34.63% Cu by mass. How many grams of Cu can be obtained from kg of the ore? g 9. [Chang7 1.P.087.] Comment on whether each of the following is a homogeneous mixture or a heterogeneous mixture. (a) orange juice homogeneous heterogeneous (b) blood homogeneous heterogeneous 10. [Chang7 1.TB.006b.] Water is an example of a

6 11. [Chang7 1.TB.007a.] The boiling point of a liquid is an example of a physical property. true false 12. [Chang7 1.TB.007b.] The density of a substance is an example of a chemical property. true false 13. [Chang7 1.TB.008a.] Which of the following is an intensive property? density mass volume length

7 14. [Chang7 1.TB.008b.] Which of the following is an extensive property? boiling point density freezing point volume 15. [Chang7 1.TB.012.] Which of the following is a chemical change? a flashlight beam slowly dims and goes out helium gas leaking from a balloon a spoonful of salt is dissolved in a bowl of soup frozen orange juice is reconstituted by the addition of water 16. [Chang7 1.TB.017a.] Which of the following is not an SI base unit? second kelvin kilogram kilometer

8 17. [Chang7 1.TB.017b.] Which of the following SI base units is not commonly used in chemistry? kelvin kilogram candela mole 18. [Chang7 1.TB.018.] Which of the following prefixes means 1/1000? kilo deci milli centi 19. [Chang7 1.TB.021.] If 586 g of bromine occupies 188 ml, what is the density of bromine in g/ml? 3.12 g/ml g/ml 31.2 g/ml 4.53 g/ml

9 20. [Chang7 1.TB.029a.] What is expressed in scientific notation? [Chang7 1.TB.029b.] What is 356 expressed in scientific notation? [Chang7 1.TB.030a.] What is expressed as a decimal?

10 23. [Chang7 1.TB.033.] Which of the following measurements has five significant figures? 4867 mi 56 ml cm 60,104 ton 24. [Chang7 1.TB.035.] What is m m m expressed in the correct units with the correct number of significant figures? m 10.6 m m 25. [Chang7 1.TB.036.] What is km 5.70 km expressed in the correct units with the correct number of significant figures? 1.28 km km

11 26. [Chang7 1.TB.040.] How many seconds are there in a solar year ( days), expressed in the correct number of significant figures? s s s s 27. [Chang7 1.TB.076.] The natural abundances of elements in the human body, expressed as percent by mass, are: oxygen (O), 65 percent; carbon (C), 18 percent; hydrogen (H), 10 percent; nitrogen (N), 3 percent; calcium (Ca), 1.6 percent; phosphorus (P), 1.2 percent; all other elements, 1.2 percent. What is the mass (in grams) of oxygen, carbon and hydrogen in the body of a 62 kg person? g O; g C; g H g O; g C; g H g O; g C; g H g O; g C; g H it all questions for grading Save all work Home My Assignments by North Carolina State University. All rights reserved.