Unit+1+-+Measurement

1) The distance between carbon atoms in ethylene is 134 picometers. Which of the following expresses that distance in meters? a. 1.34 x 10-12 m b. 1.34 x 10-13 m c. 1.34 x 10-7 m  d. 1.34 x 10-10 m e. 1.34 x 10-6 m Pico=10^-12

2) A dose of medication was prescribed to be 35 microliters. Which of the following expresses that volume in centiliters? a. 3.5 x 105 cL b. 3.5 x 104 cL c. 3.5 cL d. 3.5 x 10-4 cL  e . 3.5 x 10-3 cL to go from micro to centi is a conversion of 1 microliters = 0.0001 centiliters

3) You prepare 1000. mL of tea and transfer it to a 1.00 quart pitcher for storage. Which of the following statements is true? a. The pitcher will be filled to 100% of its capacity with no tea spilled. b. The pitcher will be filled to 95% of its capacity. c. The pitcher will be filled to 50% of its capacity. = d.  The pitcher will be completely filled and a small amount of tea will overflow.= e. The pitcher will be completed filled and most of the tea will overflow.

1 ml = 0.00105668821 US quarts, so 1000 X .oo105668821= 1.06quarts
4) In an average year the American chemical industry produces more than 9.5 million metric tons of sodium carbonate. Over half of this is used in the manufacture of glass while another third is used in the production of detergents and other chemicals. How many pounds of sodium carbonate are produced annually? a. 2.1 x 1010 lb b. 4.3 x 109 lb c. 1.1 x 107 lb d. 2.2 x 106 lb
 * e. 2.1 x 104 lb**

1 metric tons = 2 204.62262 pounds
5) The average distance between the Earth and the Moon is 240,000 miles. Express this distance in kilometers. a. 6.1 x 105 km b. 5.3 x 105 km d. 1.5 x 105 km e. 9.4 x 104 km
 * c. 3.9 x 105 km**

1 miles = 1.609344 kilometers
6) A large pizza has a diameter of 15 inches. Express this diameter in centimeters. b. 24 cm c. 18 cm d. 9.3 cm e. 5.9 cm
 * a. 38 cm**

15 inches X 2.54 centimeters= 38 after rounded

7) The speed needed to escape the pull of Earth's gravity is 11.3 km/s. What is this speed in mi/h? a. 65,500 mi/hr b**. 25,300 mi/h**r c. 18,200 mi/hr d. 1,090 mi/hr e. 5.02 x 10-3 mi/hr

8) A flask has a mass of 78.23 g when empty and 593.63 g when filled with water. When the same flask is filled with concentrated sulfuric acid, H2SO4, its mass is 1026.57 g. What is the density of H2SO4? (Assume the density of water is 1.00 g/mL). a. 1.992 g/cm3 b. 1.840 g/cm3 c. 1.729 g/cm3 d. 1.598 g/cm3 e. 0.543 g/cm3

11) Which measurement is expressed to 4 significant figures? a. 0.00423 kg b. 24.049 cm c. 1300 ºC d. 82,306 m
 * e. 62.40 g**

e. because the zero counts as long as it is after the decimal and #s one through 9 count as a figure

12) Express 96,342 m using 2 significant figures. a. 9.60 x 104 m c. 9.60 x 10-4 m d. 9.6 x 10-4 m e. 96,000 m
 * b. 9.6 x 104 m**

b. because two numbers equal two significant figures and the decimal moves to the left four spaces

13) Bud M. Chemist must determine the density of a mineral sample. His four trials yield densities of 4.77 g/cm3, 4.67 g/cm3, 4.69 g/cm3, and 4.81 g/cm3. Independent studies found the correct density to be 4.75 g/cm3. Which of the following statements represents the best analysis of the data? a. Bud’s results have much greater accuracy than precision. b. Bud’s results have much greater precision than accuracy. d. Bud’s results have low accuracy and low precision. e. Bud’s equipment is faulty.
 * c. Bud’s results have high accuracy and high precision.**

14) When applying the scientific method, it is important to avoid any form of hypothesis. a. True **b. False**

15) The number 6.0448, rounded to 3 decimal places becomes 6.045. because the second 4 rounds to 5 and the zero counts as one place
 * a. True** b. False

16) The number 6.0448, rounded to 2 decimal places becomes 6.05.

a. True **b. False**
false because the 6.0448 would round to 6.04 if it is rounded to two decimal places because the second four wouldn't round up the first four and would leave the first 4 as itself