CBSE Questions for Class 11 Medical Chemistry Classification Of Elements And Periodicity In Properties Quiz 8 - MCQExams.com

1. The name is derived directly from the atomic number of the element using the above Latin numerical roots.
   
2. The roots are put together in the order of the digits which make up the atomic number and terminated by 'ium' to spell out the name. The final 'n' of 'enn' is elided when it occurs before 'nil', and the final 'i' of 'bi' and of 'tri' when it occurs before 'ium'.
3. The symbol of the element is composed of the initial letters of the numerical roots which make up the name.
4. The root 'un' is pronounced with a long 'u', to rhyme with 'moon'. In the element names each root is to be pronounced separately.

5. Element with atomic number 117 is named as Ununseptium (Uus).

1. The name is derived directly from the atomic number of the element using the above Latin numerical roots.
   
2. The roots are put together in the order of the digits which make up the atomic number and terminated by 'ium' to spell out the name. The final 'n' of 'enn' is elided when it occurs before 'nil', and the final 'i' of 'bi' and of 'tri' when it occurs before 'ium'.
3. The symbol of the element is composed of the initial letters of the numerical roots which make up the name.
4. The root 'un' is pronounced with a long 'u', to rhyme with 'moon'. In the element names each root is to be pronounced separately.

Ionisation energy decreases down the group with increase in size. These elements belong to same group (1st). The correct order of first ionization energy should be: $$K < Na$$.

Ionisation energy increases across a period from left to right. Be lies on the right of Lithium. So Be has the highest ionisation enthalpy as the number of shell is less than Na and K. So the correct order is : $$K<Na<Be$$

Rutherfordium is a chemical element with symbol Rf and atomic number 104, named in honor of physicist Ernest Rutherford. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, 267 Rf, has a half-life of approximately 1.3 hours.

1. The name is derived directly from the atomic number of the element using the above Latin numerical roots.
   
2. The roots are put together in the order of the digits which make up the atomic number and terminated by 'ium' to spell out the name. The final 'n' of 'enn' is elided when it occurs before 'nil', and the final 'i' of 'bi' and of 'tri' when it occurs before 'ium'.
3. The symbol of the element is composed of the initial letters of the numerical roots which make up the name.
4. The root 'un' is pronounced with a long 'u', to rhyme with 'moon'. In the element names each root is to be pronounced separately.

Mendelevium is a synthetic element with chemical symbol Md (formerly Mv) and atomic number 101. A metallic radioactive transuranic element in the actinide series, it is the first element that currently cannot be produced in macroscopic quantities through neutron bombardment of lighter elements.

1. The element with the atomic number 18 is argon. It is a noble gas and belongs to zero group or 18th group. It has its octet complete and so the valency is zero.
2. Elements with atomic umber 9, 17 and 35 are F, Cl and Br. They are all halogens and belongs to group 17. All halogens have valency 1.
   
3. As the atomic size increases, electronegativity decreases. In a period electronegativity increases and in a group it decreases. Thus 17 is more electronegative than 16 and 35.
4. Hence, the correct option is $$B$$.
   

A diagonal relationship is said to exist between certain pairs of diagonally adjacent elements in the second and third periods of the periodic table. Diagonal relationships occur because of the directions in the trends of various properties as you move across or down the periodic table. Many of the chemical properties of an element are related to the size of the atom.

$$ Ca $$ and $$ Na $$ show diagonal relationship hence, similar properties. Hence, they show almost same reactivity. 

Correct Option: D

Explanation

• Electrons are filled in orbitals in accordance with three rules:
  1. Hund’s rule: It states that each orbital of a subshell should be singly occupied before pairing starts.
  2. Pauli’s exclusion principle: It states that no two electrons in an atom can have all four quantum numbers the same.
  3. Aufbau’s principle: According to this, electrons are filled in orbitals in order of their increasing energy, i.e., orbitals with lower energy must be filled before those having higher energy.
• Number of maximum electrons in each subshell:
  1. $$s= 2$$
  2. $$p= 6$$
  3. $$d= 10$$
  4. $$f = 14$$
• 
  
• The shell number from which each sub-shell begins
  1. $$s \rightarrow n = 1$$
  2. $$p \rightarrow n = 2$$
  3. $$d \rightarrow n = 3$$
  4. $$f  \rightarrow n = 4$$
  Therefore, $$3f$$ is not possible as $$f-subshell$$ begins from $$n=4$$. Only $$4f$$ and further subshells exist.

Hence, the electronic configuration which is not possible is $$3f^{12}$$

• $$O^-$$ to $$O^{2-}$$ because of interelectronic repulsion, it will require energy to add an electron to its outermost shell.
  
• Hence option B is correct answer.