The correct option is (a).
Explanation
An element is a pure substance consisting of atoms with the same number of protons. It serves as the fundamental building block of matter and is distinct from compounds or mixtures.Statement-wise Analysis:
- Statement 1 is Correct: Elements are considered the basic form of matter. Antoine Laurent Lavoisier established the definition of an element as a basic form of matter that cannot be broken down into simpler substances.
- Statement 2 is Incorrect: A defining characteristic of an element is that it cannot be broken down into simpler substances by chemical reactions. Substances that can be decomposed into simpler constituents by chemical means are known as compounds.
- Statement 3 is Incorrect: At present, there are 118 known elements listed in the Modern Periodic Table. The majority (94) occur naturally, while the remaining elements are synthetic (man-made).
Key Takeaway: Elements are the simplest chemical substances that cannot be decomposed by ordinary chemical reactions. The current scientific consensus recognizes 118 distinct elements.