# CHEM Ch. 2

 Arrange from smallest to largest: milliliter, gigaliter, microliter microlitermillilitergigaliter Arrange from smallest to largest: centigram, megagram, decigram centigramdecigrammegagram Arrange from smallest to largest: micrometer, picometer, kilometer picometermicrometerkilometer Arrange from smallest to largest: nanoliter, milliliter, centiliter nanolitermillilitercentiliter A classroom contains 63 students. a) exact number b) inexact number a) exact number The car is traveling at a speed of 56 miles per hour. a) exact number b) inexact number a) exact number The temperature on the back porch is -3 degrees F. a) exact number b) inexact number a) exact number There are 3 feet in a yard. a) exact number b) inexact number b) inexact number(it is impossible to make an exact measurement) Determine the number of significant figures: 23,009 5 Determine the number of significant figures: 0.00231 3 Determine the number of significant figures: 0.3330 4 Determine the number of significant figures: 73,000 2 Determine the number of significant figures: 73.000 2 Determine the number of significant figures: 0.40040 5 Round off to 3 significant figures: 327.123 327 Round off to 3 significant figures: 3.6007 3.60 Round off to 3 significant figures: 0.4567 0.457 Round off to 3 significant figures: 04563 456 Convert to scientific notation: 167,281.0 1.67281 x 10^5 Convert to scientific notation: 0.006024 6.024 x 10^-3 Convert to scientific notation: 19 x 10^-11 1.9 x 10^-11+1 = 1.9 x 10^-10 Convert to scientific notation: 502.6 x 10^2 5.026 x 10^2+2 = 5.026 x 10^4 What is the value of this scientific notation? 2.6 x 10^5 260,000 What is the value of this scientific notation? 1.098 x 10^-3 0.001098 Express in scientific notation: 37.22 3.722 x 10^1 Express in scientific notation: 34.000 3.4000 x 10^1 Express in scientific notation: 234,000 2.34 x 10^5 giga- G mega- M kilo- k deci- d centi- c milli- m micro- u nano- n pico- p giga- 10^9mega- 10^6kilo- 10^3deci- 10^-1centi- 10^-2milli- 10^-3micro- 10^-6nano- 10^-9pico- 10^-12 What is the higher temperature -15degC or 4degF? -15degC Air has a density of 1.29 g/L at room temp. Woud Helium gas (density = 0.18 g/L) rise or sink? rise(Helium density is less then air density) Air has a density of 1.29 g/L at room temp. Would Argon gas (density = 1.78 g/L) rise or sink? sink(Argon gas density is more than air density) Water has a density of 1.0 g/cm3 at room temp. Would Paraffin wax (density = 0.90 g/cm3) sink or float? float(Paraffin wax has less density than water density) Water has a density of 1.0 g/cm3 at room temp. Would Limestone (density = 2.8 g/cm3) wink or float? sink(Limestone density is more than water density) Mass amount of matter in an object (gram, pound, ton) Volume amount of space an object occupies (cm3, mL, Gal, L, in3)temperature dependent1.00 gal = 3.77 L1.00 mL = 1.00 cm3Length: 1.00 in = 2.54 cm Kilogram (kg) base unit of mass1889 international prototype of the kilogram is a 39 mm cylinder made of 90% platinum and 10% iridiumindependent of temperature Exact numbers Definitions - 12 objects in a dozenCounting - 15 pretzels in a bowlSimple fractions - 1/2 or 3/4 Infinite number of sig figs Significant Figures "Sig Figs" Zeros located at the beginning of a number are NEVER significantZeros located between nonzero digits are ALWAYS significantZeros located at the end of a number are significant only if the number has an explicitly shown decimal point How many sig figs? a) 3456 b) 0.048 c) 16.07 d) 9.300 e) 150 a) 4b) 2 (leading zeros do not count)c) 4d) 4 (following zeros count if number contains a decimal point)e) 2 (following zeros don't count because the number does not contain a decimal point -- in this case write in scientific notation -- 1.5 x 10^2) When multiplying exponential terms what do you do with the exponents? a) add b) subtract a) add When dividing exponential terms what do you do with the exponents? a) add b) subtract b) subtract Mass Unit Conversions 1.00 lb = 454 g1.00 kg = 2.2046 lbs1.00 oz = 28.3 g Mass vs. Weight Weight = mass X gravityAnalytical scale measures the force needed to counter sample (weight) and the acceleration of gravity. Then it solves the expression for mass which is displayed.mass = weight / acceleration due to gravitybe careful of static electricity, tilting the balance, vibrations Density Density = Mass / Volumedependent on pressure and temperature Authorkmarken ID234963 Card SetCHEM Ch. 2 DescriptionMeasurements Updated2013-09-16T02:13:29Z Show Answers