Mention a Change Which is Always,Desirable,Periodic - Chemistry

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Mention a change which is always

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Solution

  1. Desirable : Changes that are useful to man are desirable changes, e.g. change of milk into curd.
  2. Undesirable : Change that brings about destruction is an undesirable change, e.g. floods and epidemics are undesirable changes.
  3. Periodic : Changes that are repeated at regular intervals of time are called periodic changes, e.g. change of day and night.
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Chapter 2: Physical and Chemical Changes - Exercise

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Selina Concise Chemistry Class 7 ICSE
Chapter 2 Physical and Chemical Changes
Exercise | Q 3

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