• Reaction rates depend on how often particles collide and if these collisions are successful.
• Changes in reaction conditions can affect the number of collisions, their frequency, and the kinetic energy of the particles.

• More concentration = More frequent collisions = Faster reaction.
• Think of it as a crowded juice bar. More people = More orders = Faster juice-making! But if people leave (decrease in concentration), the orders slow down.

• For gases
  • More pressure = Faster reactions.
  • Less pressure = Slower reactions.
• Think of squeezing a sponge - the tighter you squeeze (more pressure), the faster the water comes out.
• Note: This doesn't apply to liquids and solids - they're like that friend who doesn't change no matter how much you "pressure" them!

• Reacting happens at the surface where different phases meet.
• A phase is a uniform substance/mixture with consistent properties.
• Breaking a solid into tiny pieces (like crushing a biscuit) increases its surface area, making reactions faster.
• Real-world example: Ever heard of grain mill explosions? That's because powdered stuff, like flour, can combust violently!

💡 Fun Fact: Magnesium ribbon reacts slower than magnesium powder. It's like how a whole chocolate bar takes longer to melt than chocolate chips!