1. The atomic radius increases on moving from left to right across a period.
2. Germanium, Tellurium, and Copper are transition metals.
3. The two isotopes of Chlorine occupy the same position in the periodic table.
4. The metallic property of Ca, Ba, Be and Sr follows the order : Be < Ca < Sr < Ba.
Select the answer using the codes given below :
Analyzing Periodic Table Statements
The question asks to identify the correct statements about the Modern Periodic Table among the given four options. Let's analyze each statement:
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Statement 1: The atomic radius increases on moving from left to right across a period.
This statement is incorrect. Across a period (left to right), the atomic number increases, leading to a stronger effective nuclear charge. This increased pull draws the electron shells closer to the nucleus, resulting in a general decrease in atomic radius.
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Statement 2: Germanium, Tellurium, and Copper are transition metals.
- Germanium (Ge) is a metalloid.
- Tellurium (Te) is a metalloid.
- Copper (Cu) is a transition metal (in the d-block).
Since Germanium and Tellurium are not transition metals, this statement is incorrect.
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Statement 3: The two isotopes of Chlorine occupy the same position in the periodic table.
This statement is correct. Isotopes are atoms of the same element with the same number of protons but different numbers of neutrons. Since the atomic number (number of protons) defines an element's position, all isotopes of an element share the same atomic number and thus the same position in the periodic table.
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Statement 4: The metallic property of Ca, Ba, Be and Sr follows the order : Be < Ca < Sr < Ba.
This statement is correct. Beryllium (Be), Calcium (Ca), Strontium (Sr), and Barium (Ba) are all in Group 2 (Alkaline Earth Metals). Metallic character increases down a group as the atomic size increases and ionization energy decreases, making it easier to lose electrons. The order of elements down Group 2 is Be, Mg, Ca, Sr, Ba. Therefore, the metallic property follows the order: Be < Ca < Sr < Ba.
Conclusion on Correct Statements
Based on the analysis, statements 3 and 4 are correct.
The correct option is the one that includes only statements 3 and 4.
Important Questions from Periodic Classification
Element X forms a chloride with the formula XCl2, which is a solid with high melting point. X would most likely be in the same group of periodic table as
- Which of the following statements is NOT correct with reference to the p-block elements?
- Where did Mendeleev arrange the elements in the periodic table with similar properties?
- What was the unknown element under aluminium called?
- What is another name for representative elements?
