Unit 1 Review. 4. Which state of matter is characterized by having a low density and high compressibility? a. solid b. liquid c. gas d.

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1 Unit 1 Review Keys to Success: 1. Review syllabus goals and key terms. 2. Review class notes for Unit Review all homework. 4. Complete review, check answers, and come in for extra help to clarify material if needed. Key Terms: chemistry, matter, substance, mass, solid, liquid, gas, vapor, physical change, physical property, intensive property, extensive property, chemical reaction, reactants, products, chemical change, chemical property, Law of Conservation of Mass, element, compound, chemical symbols, mixture, solutions, phase, heterogeneous mixture, homogeneous mixture, quantitative, precision, accuracy, percent error, meter, kilogram, absolute zero, liter, Kelvin, Celsius, conversion factor, dimensional analysis, significant figures, density 1. Matter is defined as anything that. a. has a fixed volume b. has a definite volume c. can be weighed on a balance d. has mass and takes up space 2. Let's say you had a lump of aluminum. No matter how finely you divide it, you would only have smaller pieces of... Aluminum 3. The above is a good reason to decide that aluminum is a(n) a. mixture b. compound c. element 4. Which state of matter is characterized by having a low density and high compressibility? a. solid b. liquid c. gas d. both a and b 5. Which of the following is a homogeneous mixture? a. salt water b. beef stew c. sand and water d. raisin bread 6. A glass full of liquid has an object floating half way down inside the liquid. What does this tell you about the liquid inside the glass? a. contains a pure substance b. contains a mixture c. contains an element only 7. When pure baking soda is heated, a colorless gas is given off, leaving behind a white powder which has less mass than the original baking soda. The density of the remaining white powder is g/cm 3, while the pure baking soda's density is g/cm 3. We can conclude that this new white powder and baking soda are a. the same substance. b. different substances. 8. When baking soda is heated, the resulting White powder is a. a mixture b. a compound c. an element d. can't tell from the information provided

2 9. When removing salt from salt water, one may simply boil off the water and retrieve the salt. True or False 10. The process described above works because it depends on the fact that the different parts of the mixture have different a. densities b. melting points c. boiling points 11. Would you describe the burning of charcoal as a. physical change b. chemical change c. neither d. can't tell 12. Is pure water an element, compound, or mixture? 13. Provide two examples of homogenous mixtures. Milk or blood (no visible difference) 14. Provide two examples of heterogeneous mixtures. Dirt or muddy water (Can see differences) 15. A piece of paper having a mass of 5.21 g is burnt. The remaining ash has a mass of 2.90 g. Where did the other 2.31 g go? The mass was converted into a gaseous product through a chemical reaction 16. What scientific law does the above scenario illustrate? Law of conservation of mass 17. Give an example of a mixture of three different substances consisting of at least two states of matter. Provide a short procedure describing how to use differences in physical properties to separate each substance from the mixture. A mixture of water, oil and aluminum filings. The oil is less dense than water so it will float. This will allow it to be separated from the mixture by simply pouring it off. The remaining mixture of water and aluminum can be separated by the physical property of particle size. If the mixture is passed through a filter, the water is small enough to pass through whereas the aluminum will become trapped in the filter paper. 18. Complete the following conversions using dimensional analysis.

3 19. Use dimensional analysis to convert 2.5 years into seconds. 20. Use dimensional analysis to convert 5 kg/l into g/ml. 21. Use dimensional analysis to convert 20.0 g/l into g/cm An experiment was performed to calculate the density of a solid. The solid had a mass of 25.6 g and displaced 45.0 ml of water. What is the density of the object? 23. If the accepted value for the density of solid object in the above problem is g/ml, what is the %Error in the experimentally obtained density? 24. Explain the difference between a qualitative and a quantitative measurement. Use an example to illustrate the difference. Qualitative measurements are non-numeric, subjective observations. Ex, This paper is small. Quantitative measurements contain numeric values. Ex, This paper is 8.5 inches wide 25. Explain the difference between accuracy and precision. Use an example to illustrate the difference. A measurement or value is considered accurate when it is equal to the true or accepted value. Precision occurs when a series of measurements or values are close in value. 5 different students use a specific ruler to measure the length of a nail and report values of cm, cm, cm, cm and cm. These measurements would be considered precise because they are all close in value. 26. If your teacher assigns an average of 45.0 minutes of homework per school night, how many hours of homework will his students have to do in a semester (exactly 18 weeks)? 27. If you have a part-time job that pays $9.25 an hour, and you will work 14.0 hours a week. How many weeks will you have to work to buy a $ snowboard?

4 28. Brad is watching his weight for the wrestling team, and needs to lose 5.50 pounds before wrestling season starts. He decides to cut back and drink water instead of drinking his usual two Pepsis (135 calories per Pepsi) every day. If it is possible to lose 1.00 lb. of weight by decreasing your intake by 3500 Calories, how many weeks will it take Brad to get to his wrestling weight? 29. Tina s car gets 35.0 miles per gallon on the freeway. She is driving from San Francisco to Boston (3050 miles away). She will spend an average of $3.97 per gallon of high-octane fuel. Assuming all her driving is on the freeway, how much will her trip cost in gas? 30. Jeremy runs miles per day. How many miles will he have to run in a year? 31. If your car averages about 32 miles per gallon, what is its mileage rate in kilometer/liter? (Hint: 1.61 km = 1 mi; and L = 1 qt.; 1 gallon = 4 qts.) 32. What is the volume, at room temperature, of a sample of mercury having a mass of 1.0 kg? (Mercury s density at room temperature is 13.5 g/cm 3 ) 33. How fast is 55 miles per hour (mi/hr), expressing in meters per second (m/s)? 34. The density of water is 1.00 g/cm 3. Express this density in lb/ft 3

5 35. Write the following numbers in scientific notation x x x The mass of a substance is measured three different times and determined to be 10.1 g, 10 g, and g. a. How do these numbers show precision? They are all very close to the same value. b. How do these numbers show imprecision? They are not EXACTLY the same number 37. The density of water at room temperature is 998 kg/m 3. USE DIMENSIONAL ANALYSIS a. How many kilograms of water fit in a rectangular pool measuring 10.0 m x 20.0 m x 2.0 m? b. What is the volume of the pool in liters?