How much total time was required to boil this substance after it reached its melting point? Question 4 options:

a)

2 min

b)

5 min

c)

10 min

d)

15 min

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.

Convert the temperature of dry ice, –77 ∞c, into degrees fahrenheit and kelvin.

Describe the forces both attractive and repulsive that occur as two atoms move closer together.