Aclosed system is: completely closed to the outside environment. only slightly exposed to the outside environment. in constant exchange with the environment completely exposed to the outside environment.

A closed system is completely closed to the outside environment. Every interaction is transmitted inside that closed system.

The mole unit is very important for chemical reactions, as is the skill to convert masses in g to mol. The number of moles of a substance in a sample is the mass in g divided by the molar mass, which gives the amount in moles.

Explanation:

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