What is the name of the physical change that occurs in each of the following instan a. Oxygen is cooled from -150°C to -200°C. b. Iron is cooled from 1600°C to 1500°C. C. Mercury is heated from -130°C to -100°C. 9. Which colorless substance is a solid at -50°C?

10. Which substance is a liquid at 1000°C?

11. Which substance condenses from a gas to a liquid as the temperature is cooled 20°C to -50°C?

Noble gases are the most reactive elements on the periodic table. a. true b. false

Problem page combustion of hydrocarbons such as pentane ( c5 h12 ) produces carbon dioxide, a "greenhouse gas." greenhouse gases in the earth's atmosphere can trap the sun's heat, raising the average temperature of the earth. for this reason there has been a great deal of international discussion about whether to regulate the production of carbon dioxide.(a) write a balanced chemical equation, including physical state symbols, for the combustion of liquid pentane into gaseous carbon dioxide and gaseous water. (b) suppose 0.350 kg of pentane are burned in air at a pressure of exactly 1 atm and a temperature of 20.0 degree c. calculate the volume of carbon dioxide gas that is produced.be sure your answer has the correct number of significant digits.

What is the approximate vapor pressure when the gas condenses at 70 degrees celsius