Physical and Chemical Properties of Matter Practice Accuracy, Precision, and Percent Error (Use with Notes Unit 1 Page 2)

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1 Physical and Chemical Properties of Matter Practice Accuracy, Precision, and Percent Error (Use with Notes Unit 1 Page 2) 1. The following measurements were made to determine the density of a material whose value was, according to the Handbook of Chemistry and Physics, 1.24 g/ml Trial #1: 1.20 g/ml, Trial #2: 1.22 g/ml, Trial #3: 1.22 g/ml a. Make a general comment on the accuracy of these results and on the precision of these results. b. Use the average of the three trials as the measured value and determine the numerical value for the percent error. 2. The following measurements were made to determine the density of a material whose value was, according to the handbook of Chemistry and Physics, 1.15 g/ml Trial #1: 0.95 g/ml, Trial #2: 1.16 g/ml, Trial #3: 1.26 g/ml a. Make a general comment on the accuracy of these results and on the precision of these results b. Use the average of the three trials as the measured value and determine the numerical value for the percent error. 3. In a chloride ion determination experiment, assume that when you titrated 50.0 mg/l standard chloride solution you got 46.2 mg/l. Calculate your percent error. 4. Two technicians independently measure the density of a substance. Technician A records values of 2.000, 1.999, and 2.001g/mL. Technician B records values of 2.5, 2.9, and 2.7g/mL. According to a reference table, the accepted density for the substance is 2.71g/mL. Which technician s measurements are more precise? Explain. Which technician s measurements are more accurate? Explain. 5. A gram block is placed on a balance. The balance measures the mass of the block as grams. What is the percent error of the block? 6. A teacher calculates the molar mass of sodium hydroxide as 37 g/mol. The true molar mass of sodium hydroxide is 40 g/mol. Find the teacher s percent error. 7. There are 34 questions on a test. John answers 22 of them correctly. What is John s percent error? 8. You bought a new car and estimated that your monthly payment would be $312. However, your actual payment amount is $325. How much error was in your estimate?

Significant Figures Practice (Use with Notes Unit 1 Page 3 and 4) Directions: Determine the number of significant figures in the following measurements. 1 640 cm 3 6 20.900 cm 2 200.0 ml 7 0.

000 kg m/s 2 Directions: Perform the following calculations and express the results in the correct units and number of significant figures.

2 Significant Figures Practice (Use with Notes Unit 1 Page 3 and 4) Directions: Determine the number of significant figures in the following measurements cm cm ml g/l g kg/m kg cm ,000 L kg m/s 2 Directions: Perform the following calculations and express the results in the correct units and number of significant figures. Remember, the point is to figure out how to properly round your answers! m 2.2s m m m 19 (0.054 kg kg) 5.4 m cm 35cm kg kg kg cm 2 (1.401 cm cm) kg 200m cm cm 2 28cm kg (1019m 2 40m 2 ) (54.2s 31.3s) m m L L L m (4.17 m m) m (5.022 h 4.31 h) 24 (6.23 cm cm 0.05 cm) cm Read the following to the correct number of significant figures. More practice: Determine the number of significant figures

3 1. 8,800,000,000 m Scientific Notation Practice (Use with Notes Pg 5) a. What is the coefficient for your response? b. What is the exponent for your response? kg a. What is the coefficient for your response? b. What is the exponent for your response? 3. Write each of the following in scientific notation. a. 325 b c. 70 d e. 96,400 f g. 5,921 h i. 6,587,324,000 j k l m n o. 3, p q r Write each of the following as ordinary numbers. (Watch for significant zeroes) a x10 4 b x10-4 c x10 5 d x10-2 e x10 3 f x10-1 g x10 0 h x 10-4 i x10 2 j x10-3 k x 10 5 l x 10-1 m x10 3 n x 10-2 o x10 5 p x10-3 q x 10 4 r x Round each of the following to four significant figures. a x10 5 b c x10 5 d Round each of the following to the nearest hundredth. a b c d km km km m m m cm cm cm s x10-1 L 2.36x10-4 s

4 Conversions and Dimensional Analysis Practice (Use with Notes Pg 6) 1. There are 365 days in 1 year. Write the conversion factor ratios for this relationship. 2. There are 10 decimeters in 1 meter. Write the conversion factor ratios for this relationship. 3. A student measures 5.20x10 5 cm of magnesium ribbon. Determine the length of ribbon in meters. 4. A student has 4.35x10 16 kilobytes of data stored on her computer. How many megabytes is this? 5. A balloon contains 0.5m 3 of helium gas. What is the volume of gas in cubic centimeters? 6. Three weeks ago, Andres s weight was two hundred eighty-five and two tenths kilograms. He has since lost nineteen thousand, five hundred grams. What is his current weight in kilograms? 7. Michael was collecting chicken eggs on his farm. If he collected 29 chicken eggs, how many dozen eggs does Michael have?

5 8. Convert 3,644 centimeters to meters. 9. Convert 74.5 kilometers to meters. 10. Convert 3.4 kg to pounds (lbs). 1 lb =.454 kg 11. How many ml are in a 20.0 oz soda bottle? 1 oz = ml 12. Susanna is 5.50 ft tall. What is her height in centimeters? 1 inch = 2.54 cm 13. If we are in class for 1.5 hours, how many seconds are we in class? CHALLENGE: Part 1 While playing Pokemon Go I walked about 9,000 steps in 3 hours, managed to take over a gym, and caught a wild Golduck. Over the course of the whole day, I walked 22,000 steps for about 15.2 km. Because I have run some 5K races before, I know 5 km = 3.2 miles. A) how many kilometers are in one mile? B) how many miles did I walk throughout the whole day? C) how many steps do I take for every kilometer I walk? D) how many miles did I walk in the 3 hour time period in which I took 9,000 steps? CHALLENGE: Part 2 Pokemon Go measures your distance traveled for egg hatching in a way that is designed to discourage people from playing while driving. To do this, it checks how far you have traveled in a 60 second period and will not count that distance if it is greater than 300 m. So, if the fastest you can travel and have it still count toward your egg hatching is 300 m per second, how many miles per hour is that? (Hint: You will need your answer from CHALLENGE: Part 1 A)

6 Classifying Matter Practice (Use with Notes Pg 7-13) 1. Which of water, iron, ammonia, chromium, radon, and silicon are chemical compounds as opposed to elements? A chromium and water B only water C radon and ammonia D water and ammonia E iron and silicon 2. An example of a heterogeneous mixture is A bronze. B concrete. C brass. D water. 3. How is a mixture different from a compound? A B C D Particles of a mixture are combined chemically. Components of a mixture can only be separated chemically. Components of a mixture can be separated by physical means. Composition of a mixture may be constant. 4. Identify each of the following as: element (E), compound (C), heterogeneous mix (He) or homogeneous mix (Ho) a. Table salt b. Nitric acid (HNO 3 ) c. Sugar d. Carbon Dioxide (CO 2 ) e. Milk f. Air g. Nitrogen gas (N 2 ) h. Zinc (Zn) i. Pulpy orange juice 5. Could the following be separated using physical means? Why or why not? a. b.

7 Physical/Chemical Properties/Changes Practice (Use with Notes Pg 14) Identify each of the following as a physical or chemical change and explain why. EXTENSION: Try to sketch what each change would look like for the particles! 1. You burn magnesium in oxygen using a Bunsen burner flame to form magnesium oxide. heat 2Mg(s) + O 2 (g) 2MgO(s) 2. You add zinc to hydrochloric acid to form hydrogen gas, zinc chloride, and heat. 2HCl(aq) + Zn(s) H 2 (g) + ZnCl 2 (aq) + heat 3. You combust hydrogen in oxygen using a burning splint to form water and heat. heat 2H 2 (g) + O 2 (g) 2H 2 O(g) + heat 4. You separate iron from a mixture using a magnet. magnet Fe(s) Fe(s) 5. You boil a beaker of water to form water vapor. heat H 2 O(l) H 2 O(g) 6. You mix calcium chloride with sodium carbonate to form calcium carbonate and sodium chloride. CaCl 2 (aq) + Na 2 CO 3 (aq) NaCl(aq) + CaCO 3 (s) Classify the following properties as Physical (P) or Chemical (C) and Intensive (I) or Extensive (E) 1. White phosphorous glows in the dark. 2. White phosphorous ignites (lights on fire) easily. 3. Graphite is a good industrial lubricant. 4. Strontium reacts with water. 5. Gallium has a melting point of about 86 Fahrenheit. 6. Iron rusts when it is exposed to air. 7. Diamonds are the hardest substance known to humankind. 8. Silver is a good conductor of electricity.

8 Density Practice (Use with Notes Pg 15) 1. What is the density of a block of marble that occupies 287cm 3 and has a mass of 869g? 2. A piece of wood that measures 3.0 cm by 6.0 cm by 4.0 cm has a mass of 80.0 grams. What is the density of the wood? (Volume = L x W x H) 3. Would the piece of wood described in question #2 float in water? 4. When a piece of metal with a mass of 99.43g is dropped into a graduated cylinder containing 23.55mL of water, the water level rises to 28.84mL. What is the density of the metal? 5. A cup of gold colored metal beads was measured to have a mass 425 grams. By water displacement, the volume of the beads was calculated to be 48.0 cm 3. Given the following densities, identify the metal. A B C D Gold: 19.3 g/ml Copper: 8.86 g/ml Bronze: 9.87 g/ml Lead: g/ml

Advanced Placement Chemistry ~ Summer Assignment Part 2. Name

Advanced Placement Chemistry ~ Summer Assignment Part 2 Name Topic 1: Measurements and Dimensional Analysis Appropriately read and report a measurement correctly with one uncertain digit. State the number