When a little Hg is poured into a silver nitrate solution, a tree like growth of silver ammalgam is observed. This is called the mercury tree. Hence, this option is correct.

This option is correct. When the colloidal particles are made of aggregates of atom or molecules with molecular size less than 10^-7 cm, they are known as multimolecular colloids.

This option is correct because the movement of colloidal particles is stopped by using a membrane under the influence of an electric field. The dispersion medium moves in the direction opposite to the movement of sol particles.

When the saturated solution of magnesium chloride is made to react with magnesium oxide, the resulting paste is a hard marble like mass forming MgCl₂.5MgO.xH₂O. Hence, this option is correct.

This option is correct because on heating orthophosphoric acid at 250⁰C, it loses a water molecule and forms polyphosphoric acid. It is further heated at 500⁰C to lose another molecule of water and form metaphosphoric acid. it is a glassy solid salt.

The sol is easily transformed into a suspension with the help of an electrolyte. This process is called coagulation. Hence, this option is correct.

The solution that contains more amount of solutes than the given amount of solvent, required for the saturation at a particular temperature, is called a supersaturated solution. This option is correct.

This option is correct because the mineral pyrope is the member of the garnet group. It displays red colouration in the naturals samples.

Fused quartz performs better U.V. transmission than most of the other glasses and is used to make lenses and other optics for the U.V. spectrum. It used in the manufacture of pure glasses.

This option is correct because the procces of the separation of crystalloids from colloids by diffusion through the parchment membrane is called dialysis.

This option is correct because fumed silica is also known as pyrogenic silica. It consists of droplets of amorphous silica fused into branched, chainlike, three dimensional secondary particles, which are then agglomerate into tertiary particles. The resulting powder has an extremely low bulk density and high surface area.

This option is correct because sodium hypochlorite is well known disinfectant and sterilizing agent and used extremely in bleaching cotton fibres.

This option is correct because the sodalite is a rich royal blue mineral widely enjoyed as an ornaments gemstone.

This option is correct because willemite is a zinc silicate mineral, it acts as the highly fluorescent (green) under shortwave U.V. light. These give the different colours daylight.

This option is correct because phenacites are fairly rare nesosilicate minerals consisting of the berylium orthosilicates.