Part IV - Pennies - Turn hot plate on to “3” - use steel wool to “clean up” pennies - use your forceps to place pennies into the “silver pot”

Putting It Together – COM Review Which of the following is a compound? (a) lead(c) potassium (b) wood(d) water Which of the following is a mixture? (a) water (c) wood (b) chromium(d) sulfur How many atoms are represented in the formula Na 2 CrO 4 ? (a) 3(b) 5 (c) 7 (d) 8 (d) water (c) wood (c) 7

Which of the following is a characteristic of nonmetals? (a) always a gas (b) poor conductor of electricity (c) shiny (d) combines only with metals Which of the following is a characteristic of metals? (a) ductile (b) easily shattered (c) extremely strong (d) dull (a)ductile (b) poor conductor of electricity

Chromium, fluorine, and magnesium have the symbols (a) Ch, F, Ma(c) Cr, F, Mg (b) Cr, Fl, Mg (d) Cr, F, Ma When a pure substance was analyzed, it was found to contain carbon and chlorine. This substance must be classified as (a) an element(b) a mixture (c) a compound (d) both a mixture and a compound

Coffee is an example of (a) an element (b) a compound (c) a homogeneous mixture (d) a heterogeneous mixture Sodium, carbon, and sulfur have the symbols (a) Na, C, S(c) Na, Ca, Su (b) So, C, Su (d) So, Ca, Su

The number of oxygen atoms in Al(C 2 H 3 O 2 ) 3 is (a) 2(b) 3 (c) 5 (d) 6 Which of the following is a mixture? (a) water(c) sugar solution (b) iron(II) oxide (d) iodine Which is the most compact state of matter? (a) solid (c) gas (b) liquid (d) amorphous

Part IV – continued - Turn hot plate down to “1” - use your forceps to flip pennies over - take your seat

Which is not characteristic of a solution? a) a homogenous mixture b) a heterogeneous mixture c) contains 2 or more substances d) has a variable composition A chemical formula is a combination of a) symbols b) atoms c) elements d) compounds The number of nonmetal atoms in Al 2 (SO 3 ) 3 is a) 5 b) 7 c) 12 d) 14

Which of the following is not a physical change? a) boiling point b) physical state c) bleaching action d) color Which of the following is a physical change? a)A piece of sulfur is burned b)A firecracker explodes c)A rubber band is stretched d)A nail rusts Which of the following is a chemical change? a)Water evaporates b) Ice melts c) Rocks are ground to sand d) a penny tarnishes

When 9.44g of calcium are heated in air, 13.22g of calcium oxide are formed. The percent by mass of oxygen in the compound is a) 28.6% b) 40.0% c) 71.4% d)13.2% BaI 2 contains 35.1% barium by mass. An 8.50g sample of BaI 2 contains what mass of iodine? a) 5.52g b) 2.98g c) 3.51g d) 6.49g

HgS contains 86.2% mercury by mass. The mass of HgS that can be made from 30.0g of mercury is a) 2586g b) 2.87g c) 25.9g d) 34.8g The changing of liquid water to ice is known as a a) chemical change b) heterogeneous change c) homogeneous change d) physical change

Which of the following does not represent a chemical change? a)Heating of copper in air b)Combustion of gasoline c)Cooling of red-hot iron d)Digestion of food Changing hydrogen and oxygen into water is a a)Physical change b)Chemical change c)Conservation reaction d)No correct answer given

Part IV – continued - Turn off the hot plate - Light & adjust bunsen burner - “see” the interior blue cone - “hear” it - use your forceps to remove pennies, rinse in beaker, pat dry - use your forceps to heat pennies over hottest part of flame – watch for transition & cool in beaker