Understanding Chemical Reactions: Reactants, Products, and Atom Rearrangement

What is a Chemical Reaction?

• ⚛️ A chemical reaction is a process where substances called reactants rearrange their atoms to form new substances, known as products.
• ✨ New substances are created through the breaking and forming of chemical bonds between atoms.
• 💡 Evidence of a chemical reaction can include color changes, gas production, or energy changes.

Physical vs. Chemical Changes

• 🧊 Physical changes, like breaking a salt crystal or boiling water, do not alter the identity of the substance or the arrangement of its atoms.
• 💧 In contrast, chemical changes involve a fundamental rearrangement of atoms, leading to the formation of entirely new substances with different properties.

Reactants and Products

• 🧪 Reactants are the substances present before a chemical reaction begins.
• 🌟 Products are the new substances formed after the chemical reaction has occurred.

Conservation of Mass in Chemical Reactions

• ⚖️ During a chemical reaction, atoms are only rearranged; no new atoms are created or destroyed.
• 💯 Therefore, the total mass of the reactants is equal to the total mass of the products.
• 🧱 This principle is similar to rearranging Lego bricks – the total mass of the bricks remains the same, regardless of how they are assembled.
• 💨 In open systems, the apparent mass might decrease if gases escape, but the total mass, including the gases, remains constant.