Chapter 1 Lecture Worksheet

General Chemistry I CHEM 105 Chapter 1 Lecture Worksheet NAME 1: Eli Reeder NAME 2: Chase Cornetto NAME 3: Grant Sherenbruger UNIT CONVERSIONS AND DIMENSIONAL ANALYSIS 1. The mass of a single copper atom is 1.055 * 10 ^ - 22 * s . Convert this mass to the following units: a. 1.055 * 10 ^ 22 * g = 1.055 * 0 ^ (- A) * mg b. 1.055 * 10 ^ 22 * g = 1.055 * 10 ^ - 10 PE c. 1.055 * 10 ^ 22 * g = 1.065 * 10 ^ - 16 με d. 1.055 * 70 ^ 22 * g = 1.055 * 10 ^ - 13 * ng Use a single line of dimensional analysis to solve each problem. 2. Given that there are 2.54 cm in an inch, 12 inches in a foot, and 5280 feet in a mile: a. Determine the number of centimeters in one mile. Imik 5280ft I mize 12m Ift 2.54 Jin = 160,934.4cm [1.6 x 10cm] b. Determine the number of square centimeters in one square mile. Im / (k ^ 2) * (5250n ^ 2)/(1mu ^ 2) * (12n ^ 2)/(16 ^ 2) * 2.54cm^ 2 1.n^ 2 =25,899,811,103.36 cm^ 2 [2.6 * 10 ^ 9 * c * m ^ 2] c. Determine the number of cubic centimeters in one cubic mile. 3 Imil3 5280円 120m² Imile3 x 1613 x 2.44m² = 4,168 18/83x105 X lin³ 4.7 * 10 ^ 15 * C * m ^ 3 3. What is the density of common antifreeze in units of g/mL? A 4.00-qt sample of the antifreeze weighs 9.26 lb. There are 453.59 grams per pound, 1.0567 quarts in a liter. Use a single line of dimensional analysis to solve the problem. 4 at 9.2616 1:056795 453.599 9.01 x 10-4 4. It is estimated that uranium is relatively common in the earth's crust, occurring in amounts of 4 grams per metric ton. A metric ton is 1000 kg. At this concentration, how many µg of uranium are present in 2.0 mg of the earth's crust? Use a single line of dimensional analysis to solve the problem. 49 I fon X I for 1000 X X 1600 4 10 I my 109 0.0049 Img 2,0-0,0080 y 18x10 g ug 5. Simon Newcomb calculated the speed of light in 1878 by measuring the time it took for light to travel from his lab to a mirror on the Washington Monument and back. The average measured time was 24.826 us, and the total distance that the light traveled during that time was 7.44393 km. Determine Newcomb's value for the speed of light in m/s to three significant figures. 7.44393 km 1000円 10 كس = 29984 m/s 24.826 us I km Is 6. The exertion of 25 Pascals of force distributed over 75 cm³ was able to push an object for 32 cm. Using units to guide you, and using the definition of a Pascal below, calculate an energy required to accomplish this movement. →100cm) 0.0075m² 75cm² Im 32cm 10.3 1 Pa = 1 kg m-s2 25,0075m² = 1875N 1875x.32m = 26 j MATHEMATICAL PROBLEM-SOLVING Follow a basic guideline for problem-solving, which includes the following steps: (1) represent your information with an image or diagram, (2) take note of the information you know and the information you need to figure out, (3) put your information and relationships into mathematical form, and (4) Solve the mathematics and plug in your solutions back into the diagram. Perform each step below to solve the problem. 7. Two trains are stopped on parallel tracks. The front of the engine (first car) of Train A is 1000 meters ahead of the front of the engine of Train B. The end of the caboose (last car) of train A is 400 meters ahead of the end of the caboose of Train B. Train A is exactly three times as long as Train B. How long are each of the trains? STEP1: 1000 STEP 2: Tram A 7x Train B youm STEP 3: x=3y STEP 4: 3Aty=1000m 1000-38 B+y=400m -ZA-400 Y-1000- 28=600 Train A: 900 m A=300 Train B: 300 m SIGNIFICANT FIGURES 8. For all the previous questions on this worksheet, go back and ensure each answer has the correct number of significant figures. 9. Solve for x, providing the correct number of significant figures. a. 1.42x = 3.856x + 0.052/60.1 - 2, 436x = 6.49x / (c ^ (- y)) x = - 2.66 * 10 ^ - 4 b. 1.43 * 10 ^ 4 = 0.418x - (0.0321x)/(2.315 * 10 ^ - 3) 1.43 * 10 ^ 4 =-13,448* I * 60 = x 1.43*104=* (0.418 - 0.0121/(2.515 * 12 ^ 3))