This set of Chemistry Multiple Choice Questions on “Electronic Configurations and Types of Elements: s, p, d and f Blocks”.
1. Name the element that belongs to s-block but is placed in the p-block.
a) Hydrogen
b) Helium
c) Argon
d) Aluminum
Answer: b
Clarification: Helium’s electronic configuration is 1s2. As the last electron is filled in s-orbital, it belongs to s-block. Since the 1st shell cannot accommodate any orbital than s, 1s2 is completely filled orbital, hence making it, a noble gas. Noble gases are placed in p-block.
2. __________ has both the characteristics of Alkali metals and halogens.
a) Helium
b) Chlorine
c) Sodium
d) Hydrogen
Answer: d
Clarification: As per the outer shell configuration of hydrogen (that is 1s1), it has only one electron in s-orbital making it eligible as an Alkali metal. It requires only 1 electron to obtain a noble gas configuration, which is a characteristic of halogen.
3. ns1 and ns2 are the outer shell configurations of elements in s-block.
a) True
b) False
Answer: a
Clarification: Yes, ns1 and ns2 are the outer shell configurations of elements in s-block. The reason behind this is that they are ready to lose 1 electron or 2 electrons depending on the group number and have low ionization enthalpies.
4. The p-block elements along with s-block elements are called as ________ elements.
a) Inner transition
b) Representative
c) Radioactive
d) Transition
Answer: b
Clarification: The p-block elements comprise of elements from group-13 to group-18 while s-block elements are 1st and 2nd groups. They two together form “Representative elements” or “Main group elements”.
5. What happens to the non-metallic nature as we move from left to right in groups?
a) Increases
b) Decreases
c) Remains constant
d) Irregular
Answer: a
Clarification: Non-metallic nature is defined as a tendency to gain electrons thus having high negative electron gain enthalpies, but the 18th group has no reactivity. So the non-metallic nature increases from left to right in groups leaving noble gases.
6. The outer shell electronic configuration of transition block elements is given by ________
a) (n-1)d1-10ns2
b) (n-1)d1-10(n-1)s0-2
c) (n-1)d1-10ns0-2
d) nd1-10ns0-2
Answer: c
Clarification: Transition block elemts are d-block elements. The electrons fill in the d-orbital, and s-orbital orbital gets varied for maintaing stability of atoms. Therefore the outer shell electronic configuration of transition block elements is given by (n-1)d1-10ns0-2.
7. Which of the following is not true about transuranium elements?
a) Atomic number > 92
b) Elements after Uranium
c) Decay radioactively as they are unstable
d) Example is Thorium
Answer: d
Clarification: The elements after Uranium (Z = 92) are known as transuranium elements, they are unstable and decay radioactively into other elements. But the atomic number of Thorium is 90, hence it is not a transuranium element.
8. Chalcogens are the elements of Group ___________
a) 18
b) 16
c) 12
d) 2
Answer: b
Clarification: Group 16 consists of elements that belong to chalcogens also known as the oxygen family. The elements of this group are oxygen (O), sulfur (S), selenium (Se), tellurium (Te), and Polonium (Po). They are called so because they are mostly found in earth’s crust.
9. Which of the following is not a Metalloid?
a) Germanium
b) Silicon
c) Aluminum
d) Tellurium
Answer: c
Clarification: Metalloids are those with both the properties of metals and non-metals. They are also known as Semi-metals. They are 8 metalloids known till date, namely boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), polonium (Po) and astatine (At).
10. Metals consist of ______% of the elements known.
a) 78
b) 32
c) 22
d) 68
Answer: a
Clarification: Elements are classified into metals, non-metals, and metalloids based on their properties. While 78% of the elements that are known today are metals. Metallic nature is prominent on the left side of the periodic table.