Question 3(multiple choice worth 2 points)

a 20 gram piece of metal is added to a sample of 100 grams of water inside a calorimeter. if the metal is at a temperature of -5° celsius and the water is at 20° celsius, which of the following best describes what will occur inside the calorimeter?

the final temperature of the water will be 15° celsius.
the energy gained by the metal equals the energy lost by the water.
the final temperature of the water will be higher than the initial temperature.
the temperature lost by the water will equal the temperature gained by the metal.

Draw the skeletal structures of two different molecules that are each made of 5 carbon atoms and 12 hydrogen atoms.

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.

The element that has the greatest electronegativity is