key-eng-fall07-q8059x01a4z - Many possibilities for...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
CHEM 2045C: Quiz 1 NAME _________KEY______________ N #_______________ Show your work for full credit Eng Q8059x01-alpha-4-z 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] rice pudding heterogeneous mixture [b] magnesium pure substance 2. (2 pts) In the process of attempting to characterize a substance, a chemist makes the following observations: The substance is a silver white, lustrous metal. It melts at 649 °C and boils at 1105 °C. Its density at 20 °C is 1.738 g/cm 3 . The substance burns air, producing white light. It reacts with chlorine to give a brittle white solid. The substance can be pounded into thin sheets or drawn into wires. It is a good conductor of electricity. Identify two physical properties from above, and describe those properties as intensive or extensive properties.
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Many possibilities for physical properties: White, lustrous, melts at 649 C, density is 1.738 g/cm 3 , good conductor, etc. In this example, all the properties were intensive. 3. (3 pts) Which of the following are NOT SI base units? [a] meter [e] second [b] mole [f] kilogram [c] Celsius (its Kelvin) [g] liter (derived units) [d] gram (its kilogram) [h] Kelvin 4. (3 pts) Give the number of significant figures for each number. [a] 17.06 10 3 mL [b] 0.003021 m [c] 8.30 ns 4 sig figs 4 sig figs 3 sig figs 5. (4 pts) One thousand milligrams (mg) equal one gram (g). Ten decigrams (dg) equal one gram (g). How many mg are in 143.2 dg? 1432 1 10 1000 1 14320 . dg g dg mg g mg = 6. (1 pt) What element has the chemical symbol H? Hydrogen...
View Full Document

Ask a homework question - tutors are online