Chem 1A – Physical Chemistry – Flashcards
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Classify each substance as a element, compound, homogeneous, or heterogeneous mixture
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Element: all same color Compound: 1 element combined with two others;Water Homogeneous: 2 different color scattering around Heterogeneous: 1 compound hitting another element
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Which of the following are elements?
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Correct: Silicon, lead, iodine Wrong: Water, silicone, and quartz
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Which of the following are mixtures?
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Correct: Air(N2 and O2, not bound together) and Salt Water (NaCL and h2o not bound together) Wrong: Salt and water (pure substance)
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Which of these mixtures are heterogeneous?
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Correct: Granite(appearance not uniform) Oil and water(Oil cant dissolve in water, apparent) Wrong: Brass(Solid solution from copper and zinc) Salt and Water (mix together, nothing change)
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Label each transition as a physical or chemical change
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Chemical change: 1 blue element attached to another red element. Separate elements Physical change: Element cant separate and can change from gas, liquid or solid
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Which of the following are chemical changes?
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Correct: Gasoline is burned (irreversible) Incorrect:Water is boil, gasoline evaporated, water heated up, water frozen (physical change, reversible)
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The following are properties of the metal Lithium. Classify them as physical or chemical
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Physical: Light enough to float on water,Silvery gray in color, liquid state boil at 1317, cuttable Chemical(reaction, change): Change from silvery gray to black in moist air, react violently with chlorine to form white solid, Burns in oxygen with a bright red flame, As a liquid react spontaneously with glass.
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Classify the following properties as intensive or extensive:
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Intensive: doesn't change. Boiling point, temp,color, density, hardness extensive: changes in size/amount. Volume,Mass,Length
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Hypothesis, Theory or Law
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Hypothesis: Guesses that are not verified. Theory: explanation tested and verified Law:Predicts what happen. no explanation how
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Converting standard notation---> scientific notation
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Standard: 625151 Scientific: 6.1x10^2
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Rank from least to greatest
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2.5x10^5, 6.4x10^4, 4.2x10^-2, 9.0x10^-6, 7.5x10^-6
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Identify poewr of tens that defines each prefix:
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nano:^9, kilo: ^3, centi:^-2, micro:^-6 milli:^-3 mega:^6
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0.020
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0.0 not significant. 20 significant
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Round each number to two significant figures
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233-->2.3x10^2, .0023-->2.4x10^-3, 1.005-->1.0
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To how many significant figures should each answer be rounded?
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3.98077863x10^-19---> 4 sig 2.331x10^22---> 3 sig
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Use volume to find density of rock.
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original water: 22.5 end:28 difference:5.5 59.9/5.5=10.89
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An empty beaker weighs 40.07g a) when completely filled with water, the beaker and its content have mass 346.65g. Volume of beaker if 1.00g/ml of density b)how much would the beaker and content weigh if filled with mercury, Hg=13.5g/ml
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a)346.65g-40.7g=mass of water 1/306=.00326/ml-->1/.00326=306.58ml b)306.58x13.5=4138.83+40.07=4178.9
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Which is more accurate or precise if average is 11.3
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group 1:11.5,11.3,11.1. Avg:11.3 group 2:11.5,11.4,11.4, Avg:11.4
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Temp. Conversion
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C=K-273 C=(F-32)(5/9)
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Convert meters to nanometers: .00509 meters
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1m=1000000000nm so=5090000
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Convert 7.01 km to centimeters 70.1
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7.01x1000=7010x1.x10^2=701000
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Convert 63 cubic inches to cubic feet
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63in*.00057870=.0364581
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The men's world record for swimming 1500.0 m in a long course pool is 14 min 34.56 seconds. At this rate, how many seconds would it take to swim .350 miles (1 mi=1609 m)
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.350 x 1609=563.15 meters 1500/875=563.15/x x=328.41
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If your front lawn is 18 ft wide and 20 feet long and each sq ft of lawn accumulates 1450 new snowflakes every minute, how many snow accumulates on your lawn per hour? average snowflake =2.20 mg
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360ft^2 x 1450snowflakes x 60 minute x 2.20 =68904000 mg/hr=68.904
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An office heater puts out 2050 Btus of energy int he form of heat per hour. Given that 1 btu=1.055 kj how many meagjoules of energy int he form of heat can be produced per year (365 days)
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2050 btus= (2030x1.055)kj=2141.65kJ=2141650 J=2.14165MJ 24 hr x 365 days=8760 years 2.14x8760=18834
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A 76 pound flask of Mercury costs 133.00. The density of mercury is 13.534 g/cm^3. a) Find the price of one cubic inch of mercury by calculating the following intermediate values. What is the price of one pound of mercury? What is the price of one gram of mercury What is the price of one cubic centimeter of mercury? What is the price of one cubic inch of mercury?(1cubic inch-16.387 cc) 1 pound=453.6 grams. b) it takes 3000 cubic inches of mercury to make one manometer. find the price of the mercury used to make 21 manometers by first calculating the cost of mercury for one manometer. i) what is the price of mercury used to make one manometer? ii)What is the price of mercury to make 21 manometers
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i) 133.00/76=1.75 ii)1.75/453.6 grams=.00385 iii)13.534x.00385=.0522 iv) 16.387x.0522=.8554 I) 3 cubic inch= .8554 x 3= 2.5662 ii) price of 21 manometers=2.5662 x 21= 53.8902
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While driving your rental care to Europe , you find that you are getting 13.7 km per liter of gasoline. What does this correspond to in miles per gallon?
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1km=.621 miles and 1 liters=.264 gallon 13.7x.621/.264=32.2 miles per gallon
