Preparation: 4BH3 + 3LiALH4 → 2B2H6 + 3LiF + 3AlF3 2NaBH4 +I2 → B2H6 + 2NaI + H2 2BF3 + 6NaH → B2H6 + 6NaF Structure: Diborane contains four terminal and two bridging hydrogen atoms The terminal H atoms and B atoms lie in one plane. The bridging H atoms lie above and below the plane Properties: Colourless highly toxic gas B.P : 180 K Catches Read more about Diborane Structure[…]
Sodium Hydroxide (NaOH): Also known as Caustic Soda Preparation: Sodium hydroxide is a strong base and is prepared by the electrolysis of aqueous solution of sodium chloride known as brine. NaCl is mixed in water to produce brine. Composition of brine is 25% m/m. Electrolysis of brine is carried out in an electrolytic cell known Read more about Compounds of Sodium[…]
1. Calcium oxide (Quick Lime) Lime stone found in nature is the starting material of almost all the compounds of calcium. Calcium oxide is also called Quick line. The decomposition of calcium carbonate is a reversible process CaCO₃ ⇋ CaO + CO₂ When water is added to lime, a hissing sound is produced along with Read more about Compounds of Calcium[…]
It is more harder and lighter than other alkali metals If is not affected by air easily and does not lose its lustre even on melting. It reacts slowly with water to liberate hydrogen. Lithium is the only alkali metal which directly reacts with nitrogen to form Li₃N Lithium hydroxide decomposes when heated to form Read more about Anomalous Properties of Lithium[…]
Physical properties: The hydrogen bonding between the water molecules leads to its high freezing point, high boiling point, high heat of vaporization and fusion. Covalent compounds dissolve in water due to hydrogen bonding with polar molecules. Structure of water: 1. In gas phase: Bent molecule with bond angle 104.5˚. O-H bond length: 95.7pm. Highly polar Read more about Water (H2O)[…]
It is the hardest of all alkaline earth metals. The melting and boiling points of the beryllium are the highest. It is not effected by atmosphere. It does not decompose water. It has the tendency to form covalent compounds. It does not react directly with hydrogen. It dissolves in alkaline with evolution of hydrogen. It Read more about Anomalous Behaviour of Berllium[…]
It is also called as oxygenated water (H2O – O) In its pure form it is a colorless liquid, slightly more viscous than water Structure: Hydrogen peroxide (H2O2) is a non-planar molecule. It has half opened book structure. Two oxygen atoms lying on spine of the book with O – O peroxy linkage and 2 ‘H’ atoms on each leaf of Read more about Hydrogen peroxide (H2O2)[…]
The solubility depends on a number of factors important amongst which are the lattice enthalpy of the salt and the solvation enthalpy of the ions in a solution. For a salt to dissolve in a solvent the strong forces of attraction between its ions (lattice enthalpy) must be overcome by the ion-solvent interactions. The solvation Read more about Solubility Equilibria of Sparingly Soluble Salts[…]
We know that if, ΔG is negative, then the reaction is spontaneous and proceeds in the forward direction. ΔG is positive, then reaction is considered non-spontaneous. Instead, as reverse reaction would take place ΔG is 0, reaction has achieved equilibrium; at this point, there is no longer any free energy left to drive the reaction. Read more about Relationship between equilibrium constant K, reaction quotient Q and Gibbs energy G[…]
Le Chatelier’s principle: It states that a change in any of the factors that determine the equilibrium conditions of a system will cause the system to change in such a manner so as to reduce or to counteract the effect of the change. This is applicable to all physical and chemical equilibria. 1. Effect of Read more about Factors affecting equilibria[…]