1. Chemical Formula:
* A chemical formula represents the elements present in a compound and their relative proportions.
* Elements are represented by their chemical symbols (e.g., H for hydrogen, O for oxygen, Na for sodium).
* Subscripts following the symbols indicate the number of atoms of that element in the compound.
Example:
* H₂O (water): This formula indicates that water contains two hydrogen atoms (H₂) and one oxygen atom (O). Therefore, water has two elements.
* NaCl (table salt): This formula shows one sodium atom (Na) and one chlorine atom (Cl). So, table salt has two elements.
* C₆H₁₂O₆ (glucose): This formula tells us that glucose has six carbon atoms (C₆), twelve hydrogen atoms (H₁₂), and six oxygen atoms (O₆), making a total of three elements.
2. Other Clues:
* Compound names: Sometimes the name of a compound can give you a hint. For example, "sodium chloride" clearly indicates two elements, sodium and chlorine.
Important Note:
* Elements are pure substances that cannot be broken down into simpler substances by ordinary chemical means.
* Compounds are formed when two or more different elements combine chemically in a fixed ratio.
Let me know if you'd like to practice with more examples!
