- Exam
- JEE Main
- Year
- 2024
- Date
- 27 January
- Shift
- Morning Shift
- Subject
- Chemistry
- Chapter
- d and f Block Elements
JEE Main 2024 · 27 January · Morning Shift · Chemistry · d and f Block Elements
Given below are two statements : Statement (I) : The 4f and 5f -...
Given below are two statements :
Statement (I) : The 4f and 5f - series of elements are placed separately in the Periodic table to preserve the principle of classification.
Statement (II) : s-block elements can be found in pure form in nature.
In light of the above statements, choose the most appropriate answer from the options given below:
Options
- AStatement I is false but Statement II is true
- BBoth Statement I and Statement II are true
- CStatement I is true but Statement II is false
- DBoth Statement I and Statement II are false
Correct answer
C. Statement I is true but Statement II is false
Step-by-step solution
The Lanthanides and Actinides inner transition series of elements are placed separately at the bottom of the periodic table. Reason: (i) This prevents the undue expansion of the periodic table i.e., maintains its structure and (ii) also because their properties are different from other elements.
The main reason that s-block elements never occur in free state/nature is that these are alkali and alkali earth metals which are highly reactive. The high reactivity comes from their low ionization energy.
They have either one or two electrons in their outermost orbit so they tend to form stable products as soon as they get another element wanting electrons. Thus, block elements are never found in a free state in nature.
They are always found in formed compounds, such as silicates, carbonates, oxides, etc. As the elements are highly reactive, they easily accept elements or compounds.