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In curing cement plasters water is sprinkled from time to time. This helps in

Options

  1. Akeeping it cool
  2. Bdeveloping interlocking needle-like crystals of hydrated silicates
  3. Chydrating sand and gravel mixed with cement
  4. Dconverting sand into silicic acid

Correct answer

B. developing interlocking needle-like crystals of hydrated silicates

Step-by-step solution

Water develops interlocking needle-like crystals of hydrated silicates. The reactions involved are the hydration of calcium aluminates and calcium silicates which change into their colloidal gels. At the same time, some calcium hydroxide and aluminium hydroxides are formed as precipitates due to hydrolysis. Calcium hydroxide binds the particles of calcium silicates together while aluminium hydroxide fills the interstices rendering the mass impervious.

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