Honors Chemistry Study Guide for Ch1 and 2 Test 1) Define volume, state two of its most common units, and state what two instruments can be used to measure and/or calculate volume. Volume is the amount of space an object takes up. It is often measured in a graduated cylinder or can be calculated for regular shapes using a metric ruler to measure lengths or radii and using a volume formula 2) State four lab safety instruments found in this room and explain what they are used for? Four lab safety instruments include goggles (protect eyes), aprons (protect clothes and body), fire extinguisher (put out fires), and eye wash (wash out eyes when irritated. 3) Describe how mass and weight differ and state what instruments are used to measure each? Weight is dependent on gravity and mass is not. Mass does not change anywhere in the universe. 4) What metric unit would you use to measure the a) Length of a country: km b) Mass of a chocolate chip: g c) Temperature of a warm day: ̊C d) Length of an atom: nm e) Mass of a planet: kg or Mg f) Volume of a swimming pool: L or kL 5) Under what circumstances is a pie graph usually used? Draw an example of a pie graph. Pie graphs are often used when percentages are being used in the data. 6) What kind of a graph would you use if you had data that showed the amount of money a business earned every month for the last year? Bar graph 7) What is extrapolation and interpolation? Extrapolation is the process of extending a graph past is data point in order to obtain values outside of the original data points plotted Interpolation is the process of obtaining a value found between data points plotted 8) What is the coldest temperature possible in ̊C and in K? What happens to all motion at this temperature? The coldest temperature possible is known as absolute zero and is equal to O K and -273˚C…at this temperature it is theorized that all motion ceases. 9) Bob measured a pencil on a balance and found its mass to be 10.6g. Alexis used a different balance and found the mass of the pencil to be 10.5805g. Who used the more precise balance? How many significant figures does each of these measurements have? The more precise balance is the one Alexis used (10.5805g has 6 sig. figs.). The balance reading that Bob obtained, 10.6g, has 3 sig. figs. 10) What is the temperature in K if a liquid has a temperature of 47°C? K = ̊C + 273 so K = 47˚C + 273 = 320 K 11) What is the definition of density? What are some common units for density? Density is the mass per unit of volume in a substance and its most common units are g/ml and g/cm 3. 12)Convert 43mg to kg: 13)Convert 5g/cm3 to mg/km3: 43mg x 1kg/106 mg = 4.3 x 10-5 kg 5g/cm3 x 103mg/1g x (10 5)3cm3/1 km3 = 5 x 1018 mg/km3 14) What are the two instances in which zeroes in a measurement are significant? Zeroes are significant when found between sig. figs. and when found at the end of the number and after the decimal point 15) What are the seven steps in a good scientific method? 1) Observation 2) Statement of Problem 3) Research 5) Experiment 6) Gather and Analyze Data 4) Hypothesis 7) Conclusion 16)Count the # of significant digits in each of the following: a) 28 pens ____infinite____ d) 0.00234 L ___3____ b) 68.0 m ____3_____ e) 89,004.3200 mm ___9____ c) 2100g ____2_____ f) 200.00 kg ___5___ 17) How many numbers will be to the left of the decimal in correct scientific notation? (1) 18) Put each number in correct scientific notation: a) 436.00 m __4.3600 x 102_________ b) 0.008870 g _____8.870 x 10-3______ c) 567 x 10-4 mm __5.67 x 10-2________ d) 0.09800 x 106 ___9.800 x 104_______ 19) Do each calculation below and include the correct number of significant digits in your answer and include the correct units and put your answer in correct sci. notation: a) 289.00 m x 2.35 x 10-2 m = _____6.79 x 100 m2________ b) 0.004 g / 0.0365cm3 = ______1 x 10-1 g/cm3______ c) 45.567 g + 2.34 x 101 g + 0.8 g = ____6.98 x 101 g__________ 20) Do each conversion below using dimensional analysis…answers need to include the correct number of significant digits and be in correct scientific notation: a) Convert 56 mL to nL : 56ml x 106 nl/1ml = 5.6 x 107 nl b) Convert 0.35m3 to cm3: 0.35m3 x (102)3cm3 / 1 m3 = 3.5 x 105 cm3 c) Convert 5680 kg to pg: 5680 kg x (1015)pg / 1kg = 5.68 x 1018 pg d) Convert 5m/hr to in/s: 5m/hr x 100cm/1m x 1in/2.54cm x 1hr/3600s = 5 x 10-2 in/s e) Convert 2.45 g/ml to kg/mm3: 2.45g/ml x 1kg/1000g x 1ml/1cm3 x 1cm3/ 103mm3 = 2.45 x 10-6kg/mm3 21) True or False: a) ____False___ The color of a sample is a quantitative measurement b) ___False____ The volume of a balloon increases as it is heated to higher temperatures; therefore, the volume of the balloon is the independent variable. c) __True_____ A control is the part of an experiment that the other results will be compared to. d) __True_____ Never look directly down into a test tube or beaker that is being heated or has a reaction occurring in it.