1 (part 1 of 2)-
Suppose that 4.2 L of methane at a pressure
of 884 Torr is transferred to a vessel of volume
2.4 L. What is the final pressure of methane
if the change occurs at constant temperature?
Answer in units of Torr.

2 (part 2 of 2)-
A fluorinated organic gas in a cylinder is com-
pressed from an initial volume of 950 mL at
156 Pa to 462 mL at the same temperature.
What is the final pressure?
Answer in units of Pa.

13) a 14) a15) b16) i don't know sorry17) a (maybe)

Heat is involved in chemical change in two ways; chemical changes either result in heat being added to or removed from an object, and chemical changes require a certain amount of heat before they can take place.

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Vander waals forces are inter molecular bonds that exist within molecules of the same substance. a water molecule is made up of oxygen and hydrogen atoms which share electrons between each other. the vander waals forces are forces that exist between multitude of different  molecules of water. dipole dipole forces is the type of vander waals force that exist in water. the oxygen atom which is more electronegative pulls the shared electron closer to itself thus generating a partial negative charge while the hydrogen acquire a partial positive charge. these two different charges causes attraction to occur in water molecules.