Identify common signs that a chemical reaction has occurred

The five conditions of chemical change are color change, the formation of a precipitate, formation of a gas, odor change, temperature change.

h let me think

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

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