Atoms and molecules are the basic building blocks of matter, but they differ in composition, structure, and properties.
*Atom:*
1. Smallest unit of an element
2. Consists of protons, neutrons (in nucleus), and electrons (in orbitals)
3. Has a specific atomic number (number of protons)
4. Electrically neutral (equal number of protons and electrons)
5. Examples: hydrogen (H), oxygen (O), carbon (C)
*Molecule:*
1. Group of two or more atoms chemically bonded
2. Can be composed of same (e.g., O2) or different elements (e.g., H2O)
3. Has a specific molecular formula (e.g., H2O, CO2)
4. Can be electrically neutral or charged (ion)
5. Examples: water (H2O), carbon dioxide (CO2), oxygen gas (O2)
Key differences:
1. Composition: Atoms are single elements, while molecules are combinations of elements.
2. Structure: Atoms have a nucleus and electrons, while molecules have a arrangement of atoms.
3. Properties: Atoms exhibit elemental properties, while molecules exhibit unique chemical and physical properties.
To illustrate:
– Hydrogen atom (H): highly reactive
– Hydrogen molecule (H2): stable and non-reactive
– Water molecule (H2O): liquid at room temperature, essential for life
Would you like more clarification or examples?
