<p>Chemistry Unit 1 Study Guide</p><p>Learning Targets & Sample Questions (sample problems in italics) You may use your a calculator.</p><p>1. Apply significant figures rules in all calculations. a. How many significant figures are in these measurement numbers: 2.75 x 10-3, 492, 20.3, 58,000, 2.580 x 105</p><p> b. Round: 0.34373 to 3 significant figures</p><p> c. Round 5,449 to 2 significant figures.</p><p> d. Consider multiplying 6.2 x 16.43. What s the mathematical answer? If these were measurements, (6.2 mL x 16.43 g/mL) what answer would you report, and why?</p><p> e. Write 231,000 in scientific notation, indicating 3 significant figures.</p><p>2. Be able to convert within the metric system with units for length, mass, volume and combinations of units. Understand the metric system units and multipliers (prefixes) for measuring length, volume, and mass.; e.g., for grams: 1kg = 1000 g; 1 g = 10 dg; 1 g = 100 cg; 1 g = 1000 mg. Know the meaning of the metric prefixes: kilo = 1000 or 103; deci- = 1/10 = 0.1 = 10-1; centi- = 1/100=0.01 =10-2; milli- = 1/1000= 0.001 = 10-3</p><p> a. Using different unit (prefixes), how many ways can you write 0.5 L?</p><p> b. How many meters in 120 cm? in 3.65 km?</p><p>3. Be able to use units and unit analysis (dimensional analysis) to solve problems, write conversion factors using equivalent quantities and units, and set up multiplication steps to cancel (like factors) units – showing units!</p><p> a. Convert 10.3 cm to ft. (1 in = 2.54 cm, 12 in = 1ft ) b. Convert 9.83 kg to pounds. (1 pound = 453.6 g)</p><p> c. Convert 1.83 m to inches. (1 cm = 2.54 in )</p><p>4. Be able to use the density equation D = m/vol, typical units = g/mL or g/cm3.</p><p> a. Calculate the density in g/mL or g/cm3 given mass = 234 g and volume = 2.2 cm3.</p><p> b. Calculate the density in g/mL or g/cm3 given mass = 1.2 lbs and volume = 2.2 ft3. (1 lb = 453.59 g; 1in = 2.54cm).</p><p> c. Calculate the mass in g if the density of an object is 0.88 g/ml and you have 50 mL.</p>