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Surface Chemistry — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistrySurface Chemistry3 Marks
Question
Explain the following terms giving a suitable example in each case:
  1. Emulsification.
  2. Homogeneous catalysis.
✓

Answer

  1. Emulsification - The process of making an emulsion by mixing two liquids vigoursly is known as emulsification e.g. milk, vanishing cream, cold cream, butter, etc.
  2. Homogeneous catalysis – If the catalyst is present in the same phase as the reactant. The catalysis is called homogeneous catalysis.
$\text{2CH}_{3}\text{CH}_{2}\text{OH}\text{(l)}\xrightarrow{(conc)H_{2}SO_{4}(l)}\text{C}_{2}\text{H}_{5}\text{-O-C}_{2}\text{H}_{5}\text{(l)}+\text{H}_{2}\text{O}\text{(l)}$

$\text{2SO}_{2}\text{(g)}+\text{O}_{2}\text{(g)}\xrightarrow{NO(g)}\text{2SO}_{3}\text{(g)}.$

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