मराठी
सी.आई.एस.सी.ई.आयसीएसई ICSE Class 8

How Do the Following Help in Bringing About a Chemical Change? Pressure . - Chemistry

Advertisements
Advertisements

प्रश्न

How do the following help in bringing about a chemical change?

pressure.

टीपा लिहा
Advertisements

उत्तर

Some chemical reactions take place when reactants are subjected to high pressure.
e.g: Nitrogen and hydrogen when subjected to high pressure produce ammonia gas.

\[\ce{N2+3H2⇌[450°C][200 atm] 2NH3}\]

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 6: Chemical Reactions - Exercise 1 [पृष्ठ ७३]

APPEARS IN

सेलिना Concise Chemistry [English] Class 8 ICSE
पाठ 6 Chemical Reactions
Exercise 1 | Q 3.1 | पृष्ठ ७३

संबंधित प्रश्‍न

When carbon dioxide is passed through lime water, it turns milky due to the formation of ______.


Complete and balance the following chemical equations:

`"H"_2"S"` + `"CI"_2`  `→`  


FILL IN THE BLANK

In a double decomposition precipitation reaction both the reactants must be ............ soluble.


How is precipitate formation in a chemical reaction indicated?


What are the characteristics of a chemical reaction ? A chemical reaction is characterised by an irreversible change in which a new substance is formed.


Give an example of the following chemical change.

Two solids combine to form a liquid


Give reason for the following:

Silver nitrate solution is kept in coloured bottles.


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.


Multiple choice:

Which of the following is not a characteristic of a chemical change?


Name: Two nitrates that do not produce nitrogen dioxide on heating.


Give a chemical test to distinguish between the following gases. 

H2 and CO2


On heating which of the following substances i.e. copper carbonate, zinc carbonate, washing soda, copper sulphate, zinc nitrate, copper nitrate, lead nitrate, ammonium chloride and ammonium dichromate – relate to the reaction given below.

A coloured substance which leaves on strong heating a black residue and evolves two colourless gases one of which is acidic and the other neutral.


Give balanced equation for the following conversion affected by heat alone on the substance:

Copper carbonate to copper oxide


Give balanced equation for the following conversion affected by heat alone on the substance:

Hydrated copper sulphate to sulphur dioxide


Give a balanced equation for the conversion of an ammonium salt to a basic gas.


Differentiate between the following:

Neutralization reaction and a precipitation reaction.


A thick coating of a paste of Plaster of Paris (POP) is applied over the bandage on a fractured bone. It becomes hard on drying to keep the fractured bone immobilised. Can the change in POP be reversed?


______ change results in the change of the substance.


Classify the following as physical or chemical properties

Zinc dissolves in hydrochloric acid with the evolution of hydrogen gas.


We are advised to not to play with fireworks. Give reason.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×