Using the information in the table to the right, calculate the enthalpy of combustion of each of the following substances: acetylene: kj/mol ethanol: kj/mol -1256 -1277

Describe what happens to the molecules as water goes from ice to liquid to vapor. be sure to explain what happens to the temperature during the phase changes.

Which of the following are correct values for the ideal gas laws constant r

Oil rich countries in the middle east cover about 4% of earths total land area but prossess about 48% of the worlds known oil reserves what is the main reason for high concentration of reserves in this part of the world