Unit 1 Lab Worksheet_rev2

Measurement, Numbers & Dimensional Analysis EXERCISE 1 Part 1: Measurements Observe the markings on a ruler and use the ruler to measure the following items. Item Length (m) Estimated Digit Number of Significant Figures Width of little fingernail 0.0082m 2 2 Length of a shoe 0.2842m 2 4 Your height 1.7783m 3 5 Part 2: Scientific Notation 1. Using a computer or other resource, determine the mass of earth in kg. Express this number with and without scientific notation. 5.972 ∗ 10 24 kg 5972000000000000000000000kg 2. An important number used in chemistry is Avogadro's Number which is used to describe the number of molecules in a mole of substance (we will discuss Moles in another unit of this course). Look up this number and express it with and without scientific notation. 6.022 ∗ 10 23 602200000000000000000000 3. Solve the following math problems using scientific notation: 1. 4.9 × 10 2 + 7.9 × 10 3 4.9 ∗ 10 2 = 490 7.9 ∗ 10 3 = 7900 490 + 7900 = 8390 = 8.39 ∗ 10 3

Measurement, Numbers & Dimensional Analysis 2. 4.801 × 10 3 − 2.2 × 10 7 4801 − 22000000 =− 21995199 − 2.1995199 ∗ 10 7 3. ( 9 × 10 − 1 ) × ( 3 × 10 10 ) 0.9 ∗ 30000000000 = 27000000000 2.7 ∗ 10 10 4. ( 3.5 × 10 − 6 ) ÷ ( 5 × 10 − 2 ) 0.0000035 0.05 = 7 ∗ 10 − 5 Part 3: Significant Figures 1. For the following numbers below, state the number of significant figures: 1. 0.000420 3 2. 6.02 × 10 23 3 3. 0.00230 3

Measurement, Numbers & Dimensional Analysis 5. ( 2.31 × 10 3 ) ÷ ( 3.1 × 10 2 ) 7.5 6. 1.23 × 3.456 4.25 Part 4: Length Length is defined as the measurement of something from end to end. In the SI system it is expressed in meters. The meter is the length of the path traveled by light in a vacuum during a time interval of 1/299792458 of a second. Use your textbook or the internet to determine the following: 1 in = 2.54 cm 1 mile =5280 ft 1 km = 0.62137 miles 1 furlong = 201.168 meters 1. Using a ruler to measure the length of an 8 1 2 × 11 sheet of printer paper. Take a photo of you measuring the paper. Find the relationship between centimeters and inches, and

Measurement, Numbers & Dimensional Analysis compare to the conversion above. Click or tap here to enter text. 2. Measure the width, in inches, of your desk or kitchen table using the tape-measure. Take a photo of you measuring the table or desk. Record this measurement in inches and convert it to meters. Click or tap here to enter text. 3. Measure the width of a pencil or pen in centimeters and convert it to miles. Take a photo of you measuring the pencil. Record your answer in scientific notation. Click or tap here to enter text. 4. Convert your height in inches to millimeters. Click or tap here to enter text. 5. When driving to the store, determine how long your journey is in miles. Convert this measurement to kilometers and then furlongs.

Measurement, Numbers & Dimensional Analysis Time is defined as the measured or measurable period during which an action, process, or condition exists or continues. It is measured in seconds in the SI system in which the second is the duration of 9192631770 periods of radiation corresponding to a transition between ground state levels of cesium 133. 1. How many seconds does it take the earth to make one orbit around the sun? Click or tap here to enter text. 2. How many seconds does it take the earth to make one rotation? Click or tap here to enter text. 3. How many nanoseconds are in 1 megasecond? Click or tap here to enter text. 4. One light year is the distance that light travels in exactly one year. if the speed of light is 6.7 × 10 8 mph, convert light-years to (a) miles and (b) meters. Click or tap here to enter text. Part 7: Temperature Temperature is the degree or amount of heat present in a substance. The SI unit for temperature is the kelvin, which is the fraction 1 273.15 of the temperature of the triple point of water. Absolute, or thermodynamic, temperature is conventionally measured in kelvins (Celsius-scaled increments) and in the Rankine scale (Fahrenheit-scaled increments) with increasing rarity. Absolute temperature measurement is uniquely determined by a multiplicative constant which

Measurement, Numbers & Dimensional Analysis specifies the size of the “degree”, so the ratios of two absolute temperatures, T 2 T 1 , are the same in all scales. 1. What equation can be used to convert between Celsius and Kelvin? Click or tap here to enter text. 2. What equation can be used to convert between Celsius and Fahrenheit? Click or tap here to enter text. 3. Use a thermometer to determine your actual body temperature in Fahrenheit. Convert this temperature to Celsius. Click or tap here to enter text. Part 8: Amounts The SI derived units are so named because they are obtained from the seven SI base units. Examples include area (m 2 ), volume (m 3 ), pressure (n/m 2 ), and density (kg/m 3 ). Volume Volume is the quantity of three-dimensional space occupied by a liquid, solid, or gas. The confusing unit of measure known as an ounce. Use your textbook or the internet to determine the following: 1000 mL = __________ L 1 gallon = __________ L 1 cm 3 = __________ mL