Boron atom in \(BF_3\) is \(sp ^2\) hybridized. The orbital picture of boron in the excited state can be shown as:
Nitrogen atom in \(NH_3\) is \(sp ^3\) hybridized. The orbital picture of nitrogen can be represented as:
After the reaction has occurred, an adduct \(F_3B\), \(NH_3\) is formed as hybridization of \('B'\) changes to \(sp^3\) . However, the hybridization of \('N'\) remains intact.
Match List - I with List - II.
| List - I (Complex) | List - II (Hybridisation) |
|---|---|
| (A) \([\text{CoF}_6]^{3-}\) | (I) \( d^2 sp^3 \) |
| (B) \([\text{NiCl}_4]^{2-}\) | (II) \( sp^3 \) |
| (C) \([\text{Co(NH}_3)_6]^{3+}\) | (III) \( sp^3 d^2 \) |
| (D) \([\text{Ni(CN}_4]^{2-}\) | (IV) \( dsp^2 \) |
Choose the correct answer from the options given below:
Match List - I with List - II.
List - I (Saccharides) List - II (Glycosidic linkages found)
(A) Sucrose (I) \( \alpha 1 - 4 \)
(B) Maltose (II) \( \alpha 1 - 4 \) and \( \alpha 1 - 6 \)
(C) Lactose (III) \( \alpha 1 - \beta 2 \)
(D) Amylopectin (IV) \( \beta 1 - 4 \)
Choose the correct answer from the options given below:
Concentrated nitric acid is labelled as 75% by mass. The volume in mL of the solution which contains 30 g of nitric acid is:
Given: Density of nitric acid solution is 1.25 g/mL.
Give reasons for the following.
(i) King Tut’s body has been subjected to repeated scrutiny.
(ii) Howard Carter’s investigation was resented.
(iii) Carter had to chisel away the solidified resins to raise the king’s remains.
(iv) Tut’s body was buried along with gilded treasures.
(v) The boy king changed his name from Tutankhaten to Tutankhamun.
Draw the Lewis structures for the following molecules and ions: \(H_2S\), \(SiCl_4\), \(BeF_2\), \(CO_3^{2-}\) , \(HCOOH\)
| λ (nm) | 500 | 450 | 400 |
|---|---|---|---|
| v × 10–5(cm s–1) | 2.55 | 4.35 | 5.35 |
Such a group of atoms is called a molecule. Obviously, there must be some force that holds these constituent atoms together in the molecules. The attractive force which holds various constituents (atoms, ions, etc.) together in different chemical species is called a chemical bond.
There are 4 types of chemical bonds which are formed by atoms or molecules to yield compounds.