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Metals and Non-Metals — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceMetals and Non-Metals3 Marks
Question
Name two metals which react violently with cold water. Write any three observations you would make when such a metal is dropped into water. How would you identify the gas evolved, if any, during the reaction?
✓

Answer

Sodium and potassium metals react violently with cold water Observations:
  1. Metal starts moving over the surface of water making a hissing sound.
  2. Metal starts reacting with water causing little explosions.
  3. Soon the metal catches fire and starts burning.

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