🔥 Thermochemistry — Intro#

Scope — How energy changes accompany chemical reactions and physical processes.

Key concepts#

• Energy — capacity to do work or transfer heat.
• System and surroundings — the part of the universe under study and everything else.
• Exothermic vs endothermic — energy released to or absorbed from surroundings.

Seed Q&A triads#

• Q: What does thermochemistry study?
  A: The energy changes, especially heat flow, that occur during chemical reactions and physical transformations.

• Q: What distinguishes an exothermic reaction from an endothermic one?
  A: Exothermic reactions release heat to the surroundings; endothermic reactions absorb heat from them.

• Q: Why is defining the system important?
  A: Energy changes depend on what is included as the system versus the surroundings.

Quick activities#

• Classify common processes (combustion, melting ice, dissolving salt) as exothermic or endothermic.