A reaction occurs in a calorimeter, resulting in the starting temperature of 38.8 ℃ and final temperature 21.0 ℃. What can you say about the reaction and the enthalpy change (ΔH) during the reaction?

Adrop of acetone (nail polish remover) has a mass of 35 mg and a density of 0.788 g/cm3. what is its volume in cubic centimeters?

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.

At stp, which substance is the best conductor of electricity? a. nitrogen b. neon c. sulfur d. silver