Common Chemical Compounds and Reactions

This option is correct because cobalt nitrate on heating at high temperature with zinc oxide produces cobalt zincate. This is called as Rinmann's green.

It is called blue vitriol or neela thotha.

Common salt is chemically known as sodium chloride (NaCl). It is an ionic compound formed by the neutralization reaction between sodium hydroxide and hydrochloric acid.

Hard water contains dissolved minerals, specifically calcium and magnesium salts. When heated, these minerals precipitate as carbonates, forming the white scale known as limescale.

Benzoic acid has low solubility in cold water, meaning it does not form a clear solution and instead remains as a precipitate or suspension. Sugar, baking powder, and caustic soda are highly soluble in water.

Baking soda is the common name for sodium bicarbonate (NaHCO3). It is used in cooking as a leavening agent because it releases carbon dioxide when heated or reacted with acid.

Bones and teeth are primarily composed of hydroxyapatite, which is a form of calcium phosphate. This mineral provides the structural strength and hardness required for these tissues.

The Chlor-alkali process involves the electrolysis of brine (NaCl solution) to produce caustic soda (NaOH) and chlorine gas. Aluminium is also produced industrially via electrolysis.

In this type of colloidal sols, the dispersed phase has little affinity for the dispersion medium. These colloids are easily precipitated on the addition of small amounts of electrolytes, by heating or by shaking and therefore are not stable. Once precipitated, it is not easy to reconstitute the sol by simple mixing with the dispersion medium. Hence, these sols are called irreversible sols. Examples of lyophobic sols include sols of metals and their insoluble compounds like sulphides and oxides. Lyophobic sols need stabilizing agents to keep the dispersed phase from precipitating out.

Lime water is a saturated solution of calcium hydroxide, Ca(OH)2. It is commonly used in chemistry to test for the presence of carbon dioxide.

The reaction between a fat or oil (like linseed oil) and a strong base (like caustic soda/sodium hydroxide) is called saponification, which produces soap.

Water becomes hard as it flows over rocks because it dissolves minerals, specifically calcium and magnesium carbonates or sulfates. Calcium carbonate is the most common contributor to temporary hardness.

Detergents work in hard water because their calcium and magnesium salts are soluble in water, unlike those of soap. This prevents the formation of scum, allowing the detergent to produce lather.

Sea water contains a high concentration of dissolved salts, the most abundant of which is sodium chloride, commonly known as common salt.

Soap is produced through saponification, which involves reacting fats or oils (like linseed oil) with a strong base like caustic soda (sodium hydroxide).