Question

balanced chemical equations quick check
which example is a closed system? (1 point)
○ a sealed jar of salad dressing
○ the atmosphere of a planet
○ the human body
○ a bowl of punch at a gathering

Explanation:

A closed system is one that can exchange energy but not matter with its surroundings. A sealed jar of salad dressing meets this criterion as it doesn't allow matter (the dressing components) to enter or exit. The atmosphere of a planet can exchange matter (e.g., gases can escape or enter from space). The human body exchanges both matter (e.g., inhaling oxygen, exhaling carbon dioxide, eating food) and energy. A bowl of punch at a gathering can have matter added (e.g., more punch) or removed (people taking some punch).

Answer:

a sealed jar of salad dressing