What Happens During a Chemical Reaction:
* Reactants: The starting substances in a reaction are called reactants.
* Products: The new substances formed are called products.
* Chemical Bonds: Atoms are held together in molecules by chemical bonds. These bonds store energy.
* Breaking Bonds: To form new products, the bonds in the reactants must be broken. This requires energy input.
* Forming Bonds: New bonds are formed between atoms to create the products. This releases energy.
Conditions for a Reaction to Occur:
* Collision: Reactant molecules must collide with each other with sufficient energy.
* Activation Energy: This is the minimum energy needed to start a reaction.
* Favorable Conditions: Some reactions need specific conditions like heat, light, or catalysts to occur.
Examples of Chemical Reactions:
* Burning Wood: Wood (reactant) reacts with oxygen (reactant) in the presence of heat to produce ash, carbon dioxide, and water (products).
* Rusting: Iron (reactant) reacts with oxygen (reactant) in the presence of water to form rust (product).
* Photosynthesis: Plants use sunlight (energy) to convert carbon dioxide and water (reactants) into glucose and oxygen (products).
Key Points:
* Chemical reactions involve the creation of new substances with different properties than the reactants.
* Energy is either absorbed or released during a chemical reaction.
* The rate of a reaction can be affected by factors such as temperature, concentration, and the presence of a catalyst.
