CHEM 210-- Chapter 1 Homework with 100% correct answers

Select the correct conversion factor for each step in the following roadmap for a substance with a density of 1 g/mL. volume (L) ----> volume (mL) ----> mass (g) x 1000mL / 1L x 1g / 1mL Label each step in the Scientific Method and then place the step in the correct order 1. Observations: Natural phenomena and measured events; can be stated as a natural law if universally consistent. 2. Hypothesis: Tentative proposal that explains observations. 3. Experiment: Procedure to test hypothesis; measures one variable at a time. 4. Model (Theory): Set of conceptual assumptions that explains data from accumulated experiments; predicts related phenomena. 5. Further Experiment: Tests predictions based on model. Be sure to answer all parts. Calculate the density of a solid substance if a cube measuring 2.79 cm on one side has a mass of 115 g. ________ g/cm3 Calculate the mass of a cube of the same substance measuring 7.41 cm on one side. ________ g 5.29 (g/cm3) 2152.34 (g) Select the correct conversion factor for each step in the following roadmap for a substance with a density of 1 g/mL. mass (kg)----> mass (g) ----> volume (mL) x 1000g / 1kg x 1mL / 1g Label steps 1-5 below as chemical or physical changes 1. Chemical 2. Physical 3. Chemical 4. Chemical 5. Physical Complete each of the following statements regarding the three states of matter 1. A solid has a ____________ shape that ____________ conform to the container shape. 2. A liquid has a ____________ shape that ____________ conform to the container shape, but only to the extent of the liquid's volume; that is, a liquid ____________ form an upper surface. 3. A gas has a ____________ shape that ____________ conform to the container shape, but fills the entire shape and, thus ____________ form an upper surface. 1. fixed...does not 2. varying...does 3. varying...does...does not Classify each of the following values by the number of significant figures present in each. 1 sig fig: 90 m...0.005L 2 sig fig: 12 mL...1.2 years...7.0 m^2...50. cm 3 sig fig: 40.7 g...3270 ft...2.99x10^8 m/s 4 sig fig: 0.6258 mg...2.205 lb...8.314 J/mol*K 5 sig fig: 670.90 in not used: 4x10^6 s...6.022x10^23 mol^-1 categorize each property as either physical or chemical Physical Properties: melting point density hardness color electrical conductivity Chemical Properties: flammability corrosiveness reactivity with acids Be sure to answer all parts. Identify each of the diagrams shown here as depicting a solid, liquid, gas, or mixture of two substances. Figure (a) depicts a __________. solid liquid gas mixture Figure (b) depicts a __________. solid liquid gas mixture Figure (c) depicts a __________. solid liquid gas mixture Figure (d) depicts a __________. solid liquid gas mixture (a): liquid (b): gas (c): mixture (d): solid Select the single best answer. An empty container with a volume of 150.0 cm3 is weighed and found to have a mass of 72.3 g. The container is filled with a liquid and reweighed. The mass of the container and the liquid is 203.3 g. What is the density of the liquid to the appropriate number of significant figures? 0.87 g/cm3 0.873 g/cm3 0.8733 g/cm3 0.87333 g/cm3 0.8733 g/cm3 Be sure to answer all parts. Select the SI units for expressing the following: (a) Length meter mile kilometer cm (b) Volume m3 ft3 yd3 cm3 (c) Mass kilograms ounces pounds grams (d) Time seconds months years (e) Temperature °F K °C (a) meter (b) m^3 (c) kilograms (d) seconds (e) K Be sure to answer all parts. If the average speed of a helium atom at a certain temperature is 1220 m/s, what is the speed in miles per hour? (1 mi = 1609 m) _______ × 10_______ mi/h 2.729 x 10^3 mi/h Be sure to answer all parts. Chlorine is used to disinfect swimming pools. The accepted concentration for this purpose is 1.00 ppm chlorine, or 1.00 g of chlorine per million grams of water. Calculate the volume of a chlorine solution (in milliliters) a homeowner should add to her swimming pool if the solution contains 7.50 percent chlorine by mass and there are 2.46 × 104 gallons (gal) of water in the pool (1 gal = 3.79 L; density of liquids = 1.00 g/mL). Enter your answer in scientific notation. 1.241 x 10^3 mL Be sure to answer all parts and enter your answers in scientific notation. Write the numbers represented by the following prefixes: (a) mega−, (b) kilo−, (c) deci−, (d) centi−, (e) milli−, (f) micro−, (g) nano−, (h) pico−. (a) 1 g = ______×10 ______ megagrams (b) 1 g = ______×10 ______ kilograms (c) 1 g = ______× 10 ______ decigrams (d) 1 g = ______×10 _______ centigrams (e) 1 g = ______× 10 _______ milligrams (f) 1 g = ______× 10 _______ micrograms (g) 1 g = ______×10 _______ nanograms (h) 1 g = ______× 10 _______ picograms (a) 1 g = 1 ×10 -6 megagrams (b) 1 g = 1 ×10 -3 kilograms (c) 1 g = 1 × 10 1 decigrams (d) 1 g = 1 ×10 2 centigrams (e) 1 g = 1 × 10 3 milligrams (f) 1 g = 1 × 10 6 micrograms (g) 1 g = 1 ×10 9 nanograms (h) 1 g = 1 × 10 12 picograms Select all that apply. Which of the following statements describe chemical properties? Oxygen gas supports combustion. Hydrofluoric acid reacts with glass. Fertilizers help to increase agricultural production. Water boils below 100°C on top of a mountain. Lead is denser than aluminum. Oxygen gas supports combustion. Hydrofluoric acid reacts with glass. Fertilizers help to increase agricultural production. Be sure to answer all parts. Carry out the following operations as if they were calculations of experimental results and express each answer in standard notation with the correct number of significant figures and with the correct units. Enter both the answer and the units in the answer field. (a) 5.7129 m + 0.6 m + 4.33 m _________ __ (b) 3.70 g − 2.5933 g _________ __ (c) 4.51 cm × 5.0149 cm _________ __ (a) 10.6m (b) 1.11g (c) 22.6cm Express the answers to the following calculations in scientific notation, using the correct number of significant figures. (a) 145.75 + (2.3 × 10−1) ___× 10 2 (b) 79,500 / (2.5 × 102) ____× 10 2 (c) (7.0 × 10−3) − (8.0 × 10−4) 6.2 × 10 -3 (d) (1.0 × 104) × (9.9 × 106) 9.9 × 10 10 Be sure to answer all parts. Determine the number of significant figures in each of the following measurements: (a) 4867 mi (b) 2901 g (c) 0.0000003 cm (d) 4.6 × 1019 atoms (a) 4 (b) 4 (c) 1 (d) 2 Be sure to answer all parts. Perform the following arithmetic operations, and report the results to the proper number of significant figures. 1.2302 cm × 2.413 cm × 11.299 cm _____ cm3 19.0 kg/0.036 m3 ________ × 10__ kg/m3 (Enter your answer in scientific notation.) 1.161 × 1010 kg − 1.030 × 109 kg _______× 10__ kg (Enter your answer in scientific notation.) 20.25 mL + 39.00 mL _______mL 36 cm3 + 190.5 cm3 ________cm3 33.54cm 5.3 x 10__ 1.058 x 10 10 59.25mL 227cm^3 Enter your answer in the provided box. Suppose that a new temperature scale has been devised on which the melting point of some compound (−116.3°C) and the boiling point of the same compound (77.8°C) are taken as 0°S and 100°S, respectively, where S is the symbol for the new temperature scale. Derive an equation relating a reading on this scale to a reading on the Celsius scale. What would this thermometer read at 32.3°C? 76.6 Express the following numbers in scientific notation. Make sure you use the correct number of significant figures. (a) 0. (b) 356 (c) 47,764 (d) 0.096 (a) 2.7 x 10 -8 (b) 3.56 x10 2 (c) 4.7764 x 10 4 (d) 9.6 x 10 -2