Explanation

The initial setting of cement is caused by:

• Hydration of Tricalcium Aluminate (C₃A).
• Reaction of C₃A with water, which starts rapidly after mixing.
• Formation of calcium aluminate hydrates, causing the paste to stiffen.
• Gypsum is added to slow down this reaction and prevent flash setting.

Explanation

• Cleavage is a natural plane of weakness in a stone.
• A stone tends to split along its cleavage direction.
• Cleavage is caused by the internal structure of the mineral.

Explanation

Benzene is an organic compound.

Molecular formula C3H3.

A benzene molecule is composed of six carbon atoms connected to a planar ring, each with a hydrogen atom.

Benzene is classified as a hydrocarbon because it contains only carbon and hydrogen atoms.

Empirical  Formula: C6H6

Explanation

When cream is separated from the milk,  the density of the milk increases.

Explanation

• The father of Modern Chemistry is known as Antoine Lavoisier 
• 1743 → Born in Paris, France
• 1770s → Began major experiments on combustion
• 1789 → Published Elementary Treatise of Chemistry
• 1794 → Died during the French Revolution

Last updated by NA on 23-April-2026