Question

Which of the following Statements are NOT true about the periodic table? 
A. The properties of elements are a function of atomic weights. 
B. The properties of elements are a function of atomic numbers. 
C. Elements having similar outer electronic configuration are arranged in the 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 the same as the number of atomic orbitals available in the energy level that is being filled.

• A. A, C, and E Only
• B. D and E Only
• C. A and E Only
• D. B, C, and E Only

Hint:

Remember, elements in the same period have the same principal quantum number, and elements in the same group have the same outer electronic configuration. The modern periodic table is based on atomic number, not atomic weight.

Answer 1

The Correct Option is A

Let's analyze the statements one by one:
- A: The properties of elements are a function of atomic weights* This statement is not true. The modern periodic table is organized based on atomic numbers, not atomic weights. This was a feature of the old periodic table by Mendeleev, where atomic weights were used. Therefore, A is false.
- B: The properties of elements are a function of atomic numbers This statement is true. The modern periodic table is arranged according to the atomic number (the number of protons) of elements. The properties of elements correlate with their atomic numbers.
- C: Elements having similar outer electronic configuration are arranged in the same period This statement is not true. Elements with similar outer electronic configuration are arranged in the same group (column), not period (row). Therefore, C is false.
- D: An element's location reflects the quantum numbers of the last filled orbital
This statement is true. The location of an element in the periodic table correlates with the quantum numbers of the last electron added to its electron configuration.
- E: The number of elements in a period is the same as the number of atomic orbitals available in the energy level that is being filled
This statement is not true. The number of elements in a period is based on the electron capacity of the subshells in that energy level. The first period has 2 elements (1s orbital), the second and third periods have 8 (2s and 2p or 3s and 3p orbitals), and so on. Therefore, E is false. Thus, the statements A, C, and E are not true.