key-eng-fall07-q8059x01o3x

key-eng-fall07-q8059x01o3x - Physical (many possibilities):...

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CHEM 2045C: Quiz 1 NAME ______KEY________________ N #_______________ Show your work for full credit Eng Q8059x01-omega-3-x NOTE: for multiple choice answers, there may be more than one answer. 1. (2 pts) Classify each of the following as a pure substance or a mixture. IF a mixture, indicate whether it is homogeneous or heterogeneous: [a] salt (sodium chloride, not iodized) pure substance [b] blood heterogeneous mixture 2. (2 pts) In the process of attempting to characterize a substance, a chemist makes the following observations: The substance is a green solid. It melts at 1034 °C and boils at 1542 °C. Its density at 20 °C is 2.23 g/cm 3 . The substance does not react in air at 20 °C. It reacts with fluorine gas to give a brittle yellow solid. It is a poor conductor of electricity. Identify one physical and one chemical property.
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Unformatted text preview: Physical (many possibilities): green, melts at 1034 °C, density is 2.23 g/cm 3 , poor conductor, etc. Chemical (two possibilities): no reaction in air, reacts with fluorine gas. 3. (3 pts) Which of the following are NOT SI base units? [a] liter (derived units) [e] meter [b] second [f] mole [c] Kelvin [g] Celsius (it’s Kelvin) [d] kilogram [h] gram (it’s kilogram) 4. (3 pts) Give the number of significant figures for each number. [a] 1.7230 × 10 3 mL [b] 0.00304 ms [c] 2.207 mol 5 sig figs 3 sig figs 4 sig figs 5. (4 pts) One thousand kilometers (km) equal one meter (m). One hundred centimeters (cm) equal one meter (m). How many km are in 898000 cm? 898000 1 100 1 1000 8 98 cm m cm km m km × × = . 6. (1 pt) What element has the chemical symbol C? Carbon...
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This note was uploaded on 07/10/2011 for the course CHM 2045 taught by Professor Eng during the Fall '10 term at UNF.

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