Category: science

  Molecular solids Covalent solids Metallic solids Ionic solids 1 These are made up of molecules. These are formed by the network formed by the atoms. These solids are formed in metals only by the special bonding. These are formed by the electrostatic attraction between oppositely charged ions. 2 The molecules are held by the

It is the substance that increases the rate of reaction and itself is recovered in the same amount at the ending of reaction. It lowers the activation energy by providing an alternative pathway. And makes the reactants to cross the energy barrier easily. Mostly the transition metals like Iron, Cobalt ,Nickel , Platinum etc are

In case of PCl5 the bond pairs present on the axial position suffer more repulsion than that of bond pairs present on the equatorial position. Actually each bond pair present at the axial position has to face the repulsion of three equatorial bond pairs, due to this the bond is stretched and hence the bond

In case of hydrogen iodide the bond length is larger as compared to hydrogen fluoride. As the size of fluorine is smaller than iodine, the bond between hydrogen and fluorine is stronger and have lower bond length. This makes it harder to break the bond and release H+ ions. But in case of Hydrogen iodide

1. Zinc blende – ZnS 2. Calamine – ZnCO3 Uses of Zinc metal. The zinc metal is used for the manufacture of dying or painting , also for galvanization of iron. It is also used as the outer cover of dry cell and as a cathode also. Ores of copper and their uses Copper pyrites

Void is the empty space present in the crystal lattice. It is the unoccupied space in between the lattice points. There are:- 1. Tetrahedral void 2. Octahedral void

Step 1 : Assume the percentage as grams and divide it with molar mass. Step 2: By this way you have calculated the number of moles , further divide evey term with the smallest term which you have calculated in step 1. Step 3 : Now you have the simple whole number ratio of elements

For this we have to understand that the nature of water is polar. And salt is an ionic compound which is also polar in nature. But sugar is non polar in nature and thus it have a different nature. The dissolution of substances follow a simple rule ,”Like dissolves like.” So salt will dissolve faster

Molarity : It decreases with increase in temperature. Molality : It remains constant . Doesn’t change.

Hardy-Schulze rule It has two postulates (i) The ions which carry charge opposite to the particles of sol are more effective in causing the coagulation of the solution. (ii) Coagulating power of an electrolyte is directly proportional to the fourth power of the valency of the ions causing coagulation.

On addition of gelatin , the gold solution starts behaving like a lyophilic colloid . Otherwise the gold solution is lyophillic colliod.

the process of formation of colloids.

Lyos – solution, phobic – hating(fear) Firstly in this case we have to understand that the lyophobic colloids are those in which the dispersed phase do not have affinity for the dispersion medium. So if we add any suitable electrolyte in it , the colloidal solution easily gets coagulated.