Match the each type of chemical reaction with the chemical formula model that represents it. In the models, assume that A, B, C, and D are symbols for unknown elements, and 0 represents oxygen.
combustion o
A+B - AB
decomposition
AB - A+B
double displacement O
O AB+C - AC+B
single displacement o
AB + CD - AC + BD

Yvette hangs a 2.4kg bird feeder in the middle of a rope tied between two trees. the feeder creates a tension of 480 n in each side of the the rope.

How can you increase the strength of an electromagnet?

Air is contained in a variable-load piston-cylinder device equipped with a paddle wheel. initially, air is at 400 kpa and 17°c. the paddle wheel is now turned by an external electric motor until 75 kj/kg of work has been transferred to air. during this process, heat is transferred to maintain a constant air temperature while allowing the gas volume to triple. calculate the required amount of heat transfer in kj/kg.