Author: haroonkhan

A known weight of lime is mixed with water in a beaker and the solution is decanted. The residue is dried in the sun for 8 hours, cooled and weighed. Based on the percentage of residue, the quality of lime is decided. Residue of less than 10% indicates that the lime is good, 10–20% indicates…

Sufficient water is added to lime and a ball of the size of an egg is made. It is stored for 6 hours and then placed in a basin of water. If it shows expansion and disintegration in a few minutes, it signifies Class C lime. If the expansion is less with a number of…

Hydrochloric acid of 50% strength is added to powdered lime kept in a test tube till effervescence ceases. Generally, a teaspoonful of powdered lime of about 10 cc is required. It is kept for 24 hours. The bubbling reaction indicates the presence of lime. The volume of insoluble residue signifies unwanted inert material. Class A…

Class C lime is identified by its pure white colour.

The Bureau of Indian Standards (IS: 1624–1974) provides a number of field tests for building lime, which can be easily conducted in the field. They are discussed below next Lecture=> .

1. Heat Test A piece of dry limestone is weighed and heated on an open fire for a few hours. The limestone disintegrates emitting CO2. Due to the removal of CO2 from the sample, it loses weight. The sample is weighed again. The loss of weight indicates the amount of CO2. From this, the percentage of…

Physical tests are based on the texture, appearance, colour and odour of limestone. Limestone showing amorphous textures are suitable for making lime. Chalk and fat lime deposits are white or whitish-brown or grey in colour. Magnesium limestone is distinguished from its heaviness and hardness. Limestone with white, bluish-grey, yellow or brown colours are suitable for…

Physical and chemical tests are conducted on limestone to determine their suitability.

Quicklime should be kept in air-tight vessels or in large heaps under cover; otherwise, it should be slaked soon after delivery or run into putty to prevent deterioration. Slaked lime can be stored safely for 3–4 months if packed in gunny bags lined with polythene, craft paper, etc. The storing should be done in weather-proof…

Lime easily affects the skin and also is a health hazard if breathed in. The moisture on the body reacts with lime resulting in skin diseases. This may be avoided by coating the skin with oil. Slaking of lime is an exothermic reaction, i.e., it produces a large amount of heat. Necessary precautions should be…