Building Materials MCQ Questions & Answers | Civil Engineering

Lime putty is prepared by slaking quicklime with water. During this process, quicklime (CaO) reacts vigorously with water to form calcium hydroxide [Ca(OH)₂], which is then kept under water for a period to mature and form a smooth paste known as lime putty.

Option A: Incorrect, because lime putty is not made from hydraulic lime. Hydraulic lime sets under water due to the presence of clay impurities and is not suitable for making lime putty.

Option B: Correct, because lime putty is obtained by adding quicklime to water and allowing it to slake and mature.

Option C: Incorrect, since lime putty improves with age and can be stored for a long time (even months or years) if kept properly under water.

Option D: Incorrect, because only option B is true while A and C are false.

When a tree is freshly felled, it typically contains a significant amount of moisture, often equal to or even exceeding its own dry weight.

This moisture content can be measured as:

The percentage of water relative to the dry weight of the wood.

In a freshly felled tree, the moisture content can be as high as 100% or more, meaning the water weight can equal or exceed the dry weight of the wood.

Hence, a freshly felled tree may contain water up to 100% based on its dry weight.