Question

Why tents coated with aluminium hydroxide

Answer 1

Because Aluminium hydroxide is water insoluble and water repellent. Tents and umbrella cloths are made of tightly woven fabric so that
water with its high surface tension cannot easily penetrate. But falling raindrops can overcome the surface tension and wet the fabric which will then start sleeping water to its other side.

Answer 2

⛦Hᴇʀᴇ Is Yoᴜʀ Aɴsᴡᴇʀ⚑
▬▬▬▬▬▬▬▬▬▬▬▬☟

Tents are coated with a thin layer of aluminum hydroxide because aluminium hydroxide is insoluble in water repellent.

Thus, it drains off the raindrops before they can wet the fabric.

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