General Chemistry - Online Tutor, Practice Problems & Exam Prep

Textbook Question

A scientist uses an uncalibrated pH meter and measures the pH of a rainwater sample four times. A different pH meter was calibrated using several solutions with known pH. The true pH of the rain was found by the calibrated pH meter to be 5.12. What can be said about the level of accuracy and precision of the uncalibrated pH meter? (LO 1.14) (a) The uncalibrated pH meter is accurate and precise. (b) The uncalibrated pH meter is neither accurate nor precise. (c) The uncalibrated pH meter is accurate but not precise. (d) The uncalibrated pH meter is precise but not accurate.

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Textbook Question

Assume that you have two graduated cylinders, one with a capacity of 5 mL (a) and the other with a capacity of 50 mL (b). Draw a line in each, showing how much liquid you would add if you needed to measure 2.64 mL of water. Which cylinder will give the more accurate measurement? Explain.

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Textbook Question

Indicate which of the following are exact numbers: (a) the mass of a 3- by 5-in. index card, (b) the number of ounces in a pound, (c) the volume of a cup of Seattle's Best coffee, (d) the number of inches in a mile, (e) the number of microseconds in a week, (f) the number of pages in this book.

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Textbook Question

Indicate which of the following are exact numbers: (a) the mass of a 32-oz can of coffee, (b) the number of students in your chemistry class, (c) the temperature of the surface of the Sun, (d) the mass of a postage stamp, (e) the number of milliliters in a cubic meter of water, (f) the average height of NBA basketball players.

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Textbook Question

What is the number of significant figures in each of the following measured quantities? (e) 92.03 km

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Textbook Question

What is the number of significant figures in each of the following measured quantities? (d) 2.94 * 103 m2

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Textbook Question

What is the number of significant figures in each of the following measured quantities? (b) 3ⅹ10^-6 m

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Textbook Question

Indicate the number of significant figures in each of the following measured quantities: (e) 89.2 metr ic tons

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Textbook Question

Round each of the following numbers to four significant figures and express the result in standard exponential notation: (e) −0.0357202.

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Textbook Question

Round each of the following numbers to four significant figures and express the result in standard exponential notation: (a) 102.53070

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Textbook Question

(a) The diameter of Earth at the equator is 7926.381 mi. Round this number to three significant figures and express it in standard exponential notation.

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Textbook Question

Two students determine the percentage of lead in a sample as a laboratory exercise. The true percentage is 22.52%. The students' results for three determinations are as follows: (1) 22.52, 22.48, 22.54 (2) 22.64, 22.58, 22.62 (b) Precision can be judged by examining the average of the deviations from the average value for that data set. (Calculate the average value for each data set; then calculate the average value of the absolute deviations of each measurement from the average.) Which set is more precise?

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Textbook Question

Is the use of significant figures in each of the following statements appropriate? (a) The 2005 circulation of National Geographic was 7,812,564.

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Textbook Question

For each number, underline the zeroes that are significant and draw an x through the zeroes that are not. a. 1,050,501 km b. 0.0020 m c. 0.000000000000002 s d. 0.001090 cm

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Textbook Question

How many significant figures are in each number? a. 0.1111 s b. 0.007 m c. 108,700 km d. 1.563300 * 1011 m e. 30,800

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Textbook Question

How many significant figures are in each number? a. 0.1111 s b. 0.007 m c. 108,700 km d. 1.563300 * 1011 m e. 30,800

Which numbers are exact (and therefore have an unlimited number of significant figures)? a. p = 3.14 b. 12 in = 1 ft c. EPA gas mileage rating of 26 miles per gallon d. 1 gross = 144

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Textbook Question

Which numbers are exact (and therefore have an unlimited number of significant figures)? a. p = 3.14 b. 12 in = 1 ft c. EPA gas mileage rating of 26 miles per gallon d. 1 gross = 144

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Textbook Question

Round each number to three significant figures. a. 79,845.82 b. 1.548937 * 107 c. 2.3499999995 d. 0.000045389

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Textbook Question

Which of the following statements uses exact numbers? (a) 1 ft = 12 in. (b) 1 cal = 4.184 J (c) The height of Mt. Everest is 29,035 ft. (d) The world record for the 1-mile run, set by Morocco's Hicham el Guerrouj in July 1999, is 3 minutes, 43.13 seconds

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Textbook Question

How many significant figures are in each of the following measurements? (f) 3.8200 * 103 L

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Textbook Question

How many significant figures are in each of the following measurements? (e) 67,000 m2

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Textbook Question

How many significant figures are in each of the following measurements? (d) 0.004 50 m

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Textbook Question

How many significant figures are in each of the following measurements? (c) 0.030 03 kg

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Textbook Question

How many significant figures are in each of the following measurements? (b) 59.0001 cm

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Textbook Question

How many significant figures are in each of the following measurements? (a) 35.0445 g

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Textbook Question

How many significant figures are in each of the following measurements? (f) 10 students

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Textbook Question

How many significant figures are in each of the following measurements? (e) 5.10 * 102 J

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Textbook Question

How many significant figures are in each of the following measurements? (d) 510 J

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Textbook Question

How many significant figures are in each of the following measurements? (b) 2000.003 g

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Textbook Question

How many significant figures are in each of the following measurements? (a) $130.95

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Textbook Question

How many significant figures are in each of the following measurements? (c) 5 ft 3 in.

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Textbook Question

The Vehicle Assembly Building at the John F. Kennedy Space Center in Cape Canaveral, Florida, is the largest building in the world, with a volume of 3,666,500 m3 (a) Round off this quantity to four significant figures and then to two significant figures.

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Textbook Question

The diameter of the Earth at the equator is 7926.381 mi. (a) Round off this quantity to four significant figures and then to two significant figures.

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Textbook Question

Round off the following quantities to the number of signifi-cant figures indicated in parentheses. (d) 2.309 85 * 10-4 kg (5)

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Textbook Question

Round off the following quantities to the number of signifi-cant figures indicated in parentheses. (c) 4.995 * 103 cm (3)

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Textbook Question

Round off the following quantities to the number of signifi-cant figures indicated in parentheses. (b) 68.507 g (2, 3)

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Textbook Question

Round off the following quantities to the number of signifi-cant figures indicated in parentheses. (a) 35,670.06 m (4, 6)

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Textbook Question

Round off the following quantities to the number of signifi-cant figures indicated in parentheses. (d) 2,300,000.1 (7)

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Textbook Question

Round off the following quantities to the number of signifi-cant figures indicated in parentheses. (c) 13.2151 g/cm3 (3)

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Textbook Question

Round off the following quantities to the number of signifi-cant figures indicated in parentheses. (b) 1.605 km

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Textbook Question

Round off the following quantities to the number of signifi-cant figures indicated in parentheses. (a) 7.0001 kg (4)

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Textbook Question

Judge the following statements as true or false. If you believe a statement to be false, provide a corrected version. (g) The number 0.0033 has more significant figures than 0.033.

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Open Question

How many significant figures are in the measurement 603.040 g ?

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Open Question

Indicate the number of significant figures in each of the following

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Open Question

Determine the number of significant figures in each of the following measurements