Which of the following Statements are NOT true about the periodic table?
A. The properties of elements are function of atomic weights.
B. The properties of elements are function of atomic numbers.
C. Elements having similar outer electronic configuration are arranged in same period.
D. An element's location reflects the quantum numbers of the last filled orbital.
E. The number of elements in a period is same as the number of atomic orbitals available in energy level that is being filled.
Choose the correct answer from the options given below:
A. The properties of elements are function of atomic weights.
B. The properties of elements are function of atomic numbers.
C. Elements having similar outer electronic configuration are arranged in same period.
D. An element's location reflects the quantum numbers of the last filled orbital.
E. The number of elements in a period is same as the number of atomic orbitals available in energy level that is being filled.
Choose the correct answer from the options given below:
- (A)A, C and E Only✓ Correct
- (B)D and E Only
- (C)A and E Only
- (D)B, C and E Only
Answer: (A)
Solution
Check each statement against the modern periodic law.
A. Properties of elements are a periodic function of atomic number, not atomic weight — atomic weight was Mendeleev's earlier, superseded criterion — not true.
B. Properties being a function of atomic number is exactly the modern periodic law — true.
C. Elements with similar outer (valence) electronic configuration are placed in the same group, not the same period; period membership is instead fixed by the number of shells (the value of ) — not true.
D. The period number equals the principal quantum number of the valence shell, and the block (s, p, d, f) shows which subshell is being filled, so an element's position does reflect the quantum numbers of its last-filled orbital — true.
E. The number of elements in a period equals twice the number of orbitals available in the shell being filled, since each orbital holds two electrons by the Pauli principle, not simply the number of orbitals — not true.
The statements that are NOT true are A, C and E.
A. Properties of elements are a periodic function of atomic number, not atomic weight — atomic weight was Mendeleev's earlier, superseded criterion — not true.
B. Properties being a function of atomic number is exactly the modern periodic law — true.
C. Elements with similar outer (valence) electronic configuration are placed in the same group, not the same period; period membership is instead fixed by the number of shells (the value of ) — not true.
D. The period number equals the principal quantum number of the valence shell, and the block (s, p, d, f) shows which subshell is being filled, so an element's position does reflect the quantum numbers of its last-filled orbital — true.
E. The number of elements in a period equals twice the number of orbitals available in the shell being filled, since each orbital holds two electrons by the Pauli principle, not simply the number of orbitals — not true.
The statements that are NOT true are A, C and E.
JEE Main · 2025 · 24 Jan 2025 · Shift 1 · Single correct option