Homework due Monday, July 1

ISCS pg. 82-83, #9-19

9.  •20 x 55 = 11 sugar

     •55-11 = 44 water

     •11g sugar, 44g water. 

10. 15,000ppm

11. Water has an uneven amount of electrical charge; the end of the oxygen atom is negatively charged and the end of the hydrogen atom is positively charged. Therefore, the water molecule is a polar molecule.

12. DRAWING

13. a. The negatively charged end which is the oxygen end.

     b. The positively charged end which is the hydrogen end.

14. Heavy metals are called heavy because their atoms have a greater mass than ones with essential metallic elements; therefore, heavy metals are dangerous to humans and other things. 

15) 3 symptoms of heavy metal poisoning are tunnel vision, numbness, and brain damage.

16)

a. Humans were probably exposed to lead because since lead is in gasoline to make it more efficient, the lead entered the atmosphere through automobile exhaust as lead oxide.

b. Humans were probably exposed to mercury because mercury was in fluorescent light bulbs.

17) Hydroxide ions (OH-) are found in many bases.

18) Hydrogen (H) is found in many acids.

19)

a. basic

b. basic

c. acidic

d. chemically neutral

20) 

a. tomato

b. black coffee

c. milk of magnesia

21) 20 times more acidic.

22)

Acidic: Fish egg development is impaired, the fish cannot reproduce, fish are intoxicated when aluminum ions are present in high concentration.

23) A polar molecule is a molecule with both a positive and negative charge because of an uneven distribution of electrical charge. For example: in water there are 2 hydrogen molecules and 1 oxygen molecule. A nonpolar molecule is a molecule that has an even distribution of electrical charge an no separate sides with positive and negative charge.

24) I would choose lamp oil to dissolve a non polar molecule because it is non polar because non-polar molecules do not dissolve well in ethanol or water since those solutions are both polar.

25) NaCl is a polar molecule; thus, it dissolves in water (also polar). But, oil is non polar so it does not dissolve well in water.

26) The phrase “like dissolves like,” exhibits the pattern of solubility behavior. Polar substances dissolve is polar solvents and non polar substances dissolve in non polar solvents.

27) Water is made of polar molecules, but grease is composed of non polar molecules; thus, the water would not be able to dissolve the oil off the pan. To get the grease off, you would have to be clean the dish with a non polar substance.

33)

a. Non polar materials would probably be found in these cleaners.

b. These cleaners are non polar and could dissolve the grease off their hands; water is polar so it would not be able to dissolve the grease.

35) I would expect Hydrogen to have a partial positive charge because the electron density is much bigger than Fluorine's density.  

The solubility curve lab begins with collecting experimental data to construct a solubility curve for succinic acid, a molecular compound.