Question

which statement describes the law of conservation of energy?
○ all systems will exchange matter and energy with their surroundings.
○ all systems can exchange energy, but not matter, with their surroundings.
○ energy cannot be created nor destroyed, but it changes from one form to another.
○ energy is destroyed in most chemical reactions when new products are formed.

Explanation:

To determine the correct statement about the law of conservation of energy, we analyze each option:

• The first option is incorrect as not all systems exchange matter (e.g., closed systems don't exchange matter).
• The second option is about system types (open/closed) and not the law of conservation of energy.
• The third option correctly states the law: energy is conserved, meaning it can't be created or destroyed, only transformed between forms.
• The fourth option is incorrect because energy is never destroyed in reactions, only transformed or transferred.

Answer:

C. Energy cannot be created nor destroyed, but it changes from one form to another.