Which group of elements has a stable number of electrons in their outer energy level?
a. noble gases
c. halogens
b. alkali metals
d. alkaline earth metals

The drawing represents the movement of particles in a substance. what changes of state can this substance undergo

6. using 3 – 4 sentences explain (in your own words) why water expands when it freezes? 7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation.

Anthracite is so hard and pure it is also referred to as a renewable resource metamorphic rock hot bituminous coal dirty fuel