• Entropy measures how energy or matter is spread out.
• Spontaneous reactions 👉 More entropy!
• State changes (like from solid to liquid) 👉 Change in entropy.

• Chemical reactions can be spontaneous (they just happen!) or need a little push.
• We can tweak things like temperature, pressure, or reactant concentration to nudge reactions along.

Example: Imagine you're sliding down a playground slide. On a smooth slide, you'll glide down (spontaneous), but if there's sticky gum, you might need a push (non-spontaneous)!

• Exothermic: releases heat. Often spontaneous.
• Endothermic: needs heat. Not always spontaneous.

Real-world Example: Think of exothermic reactions like lighting a match. It gives off heat! On the other hand, endothermic reactions are like ice packs that absorb heat to cool down an injury.

Entropy (S): A measure of how scattered or disordered energy/matter is.

• Low entropy: energy and matter are in one cozy corner.
• High entropy: energy and matter throw a wild party everywhere.

Example: Imagine your room. A tidy room (everything in its place) has low entropy, while a messy room (toys and clothes everywhere) has high entropy. Your mom might not like it, but nature sure does!