Objective 2:

1.  Well a chemical and physical change are very different.  A chemical change is when something that is inside of something else changes like the particles or mineral things that are in it change.  A physical change is something that you can see.  It is like if I died my hair green, you can see the difference on the external or the outside of me.    http://wiki.answers.com/Q/The_main_difference_between_a_physical_and_a_chemical_change_is&alreadyAsked=1&rtitle=What_is_the_main_difference_between_a_physical_change_and_a_chemical_change
2.  A chemical change can occor in four ways.  One ways is that a solid is made.  Another is that an object changes color.  The third way is that gases are formed and made.  The last way is that light, sound, and/or heat are made.
http://wiki.answers.com/Q/Four_ways_you_can_tell_a_chemical_change_has_taken_place
3.  The law basically said that in a closed object that the mass of that object will stay the same.  It was made by ancient Greek philosophy people but one man's name that helped a lot was Epicurus.
http://en.wikipedia.org/wiki/Conservation_of_mass
4.  Tempature and thermal energy are very different.  Tempature is when how hot something is, is the  average of kinetic energy.  Themral energy is averaged with kinetic energy and all the other different types of energy.
http://wiki.answers.com/Q/How_is_temperature_and_thermal_energy_different
5.  Exothermic-A lizard is exothermic because it uses the sun to get body heat.
     Endothermic-We are endothermic because we make our own body heat.