System vs Surrounding

[Maria Bajenov 1I]

In a given problem, how can you determine what is the system and what is the surroundings? When it states that a reaction occurs in the flask, how do you know that the surrounding is the flask, not the lab?

[Chem_Mod]

In this case, our system would be the reaction and the surrounding would be the environment in which the reaction takes place. If the reaction is exothermic, the immediate surroundings that would absorb the heat from the reaction would be the inside of the flask.

The surroundings are considered to be everything that is not directly involved in the reaction.

[Shawn Patel 1I]

Hey,
In that reaction in a beaker, it is assumed that the beaker is the surrounding because the system (the reaction) is specifically said to be contained inside the beaker. When a system is contained in something, like a piston, that is usually the surrounding.

[Ramya Lakkaraju 1B]

Is there ever a situation in which the entire beaker would be the system and for example, the Earth would be the surroundings?

[Laura Riccardelli]

I think that they would tell us if it was not obvious what the system and surroundings are.