When 0.455 g of anthracene, C14H10, is combusted in a bomb calorimeter that has a water jacket containing 500. g of water, the temperature of the water increases by 8.63C.
Assuming that the specific heat of water is 4.18 J/(g C), and that the heat absorption by the calorimeter is negligible, estimate the enthalpy of combustion per mole of anthracene.
A) +39.7 kJ/mol
B) -39.7 kJ/mol
C) -7070 kJ/mol
D) -8120 kJ/mol
Question 2
A 255 mL round-bottom flask is weighed and found to have a mass of 114.85 g. A few milliliters of an easily vaporized liquid are added to the flask and the flask is immersed in a boiling water bath.
All of the liquid vaporizes at the boiling temperature of water, filling the flask with vapor. When all of the liquid has vaporized, the flask is removed from the bath, cooled, dried, and reweighed. The new mass of the flask and the condensed vapor is 115.23 g. Which of the following compounds could the liquid be? (Assume the ambient pressure is 1 atm.) A) C4H10
B) C3H7OH
C) C2H6
D) C2H5OH
E) C4H9OH
The water cycle.
2-1b Structure of the water molecule
Water Hole
This lithograph by Currier and Ives gives an erroneous impression of the “battle.” Major Robert Ande
Sodium has a strong reaction to water
A 400-g piece of metal at 120°C is dropped into a cup containing 450 g of water