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सी.आई.एस.सी.ई.आयसीएसई ICSE Class 7

State Four Conditions Necessary for Chemical Reactions to Take Place. - Chemistry

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प्रश्न

State four conditions necessary for chemical reactions to take place.

एका वाक्यात उत्तर
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उत्तर

Conditions necessary for chemical reactions :

  1. Close contact
  2. Solution form
  3. Heat
  4. Light
  5. Catalyst
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पाठ 5: Language of Chemistry - Exercise

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सेलिना Concise Chemistry [English] Class 7 ICSE
पाठ 5 Language of Chemistry
Exercise | Q 2

संबंधित प्रश्‍न

State whether the following statement is true or false. In case a statement is false, write the corrected statement.

Condensation of steam is not a chemical change.


Name three biochemical catalysts found in the human body.


Give reason .

A person suffering from acidity is advised to take an antacid.


FILL IN THE BLANK

........... electrolytes dissociate completely in aqueous state and allow large amount of electricity to flow through it.


Fill in the blank:
The substances which undergo chemical change are called _______


A solution of a substance ‘X’ is used for white washing write the reaction of the substance ‘X’ named in (a) above with water.


Give an example of a reaction where the following are involved:

Close contact


Give reason for the following:

Colourless concentrated sulphuric acid in a test tube changes to blue on adding a small piece of copper to it.


Give one example electrochemical reaction.


Complete and balance the following reaction:

\[\ce{NH3 + O2 ->[\Delta]}\]


Give a chemical test to distinguish between the following gases. 

SO2 and Cl2 


Give reason for the following:

Electrolytic decomposition of water is a reaction involving change of state.


Name the following:

The type of change physical or chemical involved – ‘during respiration in human beings’.


A chemical reaction is often accompanied by external indications or characteristics which include – 

  1. Colour change
  2. Effervescence or gas evolved
  3. Evolution or absorption of heat
  4. Formation of a precipitate.

With reference to each of the above indications, state the external indication seen during – Addition of dilute acid to an active metal.


Complete the table given below.

Addition of dil. H2SO4 to FeS  Odour of gas evolved  

Write some materials prepared by chemical changes.


A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.

Are these changes chemical in nature?


How would you show that the settling of curd is a chemical change?


Why is spoiling food a chemical change?


Acid rain is a result of ______.


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