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Atoms and Molecules — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceAtoms and Molecules5 Marks
Question
Write the formulae of the following compounds. Also name the elements present in them.
  1. Water.
  2. Ammonia.
  3. Methane.
  4. Sulphur dioxide.
  5. Ethanol.
✓

Answer

  1. Water: H2O; Elements present are Hydrogen and Oxygen.

  2. Ammonia: NH3; Elements present are Nitrogen and Hydrogen.

  3. Methane: CH4; Elements present are Carbon and Hydrogen.

  4. Sulphur dioxide: SO2; Elements present are Sulphur and Oxygen.

  5. Ethanol: C2H5OH; Elements present are carbon, hydrogen and oxygen.

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