Consider a ptfe molecule adjacent to a pvc molecule. select all of the secondary bonding types that exist between these two molecules. a. covalent bonding b. interactions between dipoles that are temporarily induced c. interactions between permanent dipoles d. ionic e. interactions between temporarily induced and permanent dipoles f. metallic bonding g. hydrogen bonding

Determine whether or not it is possible to compress air adiabatically from k to 140 kpa and 400 k. what is the entropy change during this process?

Athin walled concentric tube exchanger is used to cool engine oil from 160°c to 60°c with water that is available at 25°c acting as a coolant. the oil and water flow rates are each at 2 kg/s, and the diameter of the inner tube is 0.5 m and the corresponding value of the overall heat transfer coefficient is 250 w/m2. oc. how long must the heat exchanger be to accomplish the desired cooling? cpwater=4.187 kj/kg-candcpengine el=2.035 kj/kg·°c, oil . 120]

What is the heat treatment of metals? what is the benefit of it? why and how it's useful? answer in details, do not write by hand.