English

Name a Chemical Change Which Takes Place in Presence Of:

Advertisements
Advertisements

Question

Name a chemical change which takes place in presence of:

Short/Brief Note
Advertisements

Solution

Heat:

  1. Burning of paper.
  2. Cooking of food need heat.

Light :

  1. Formation of food by plants i.e. photosynthesis need light.
  2. Hydrogen and chlorine react in presence of light

Electricity:

  1. Water breaks into hydrogen and oxygen on passing electricity.
  2. Sodium chloride solution breaks up into its components sodium and Chlorine on passing electric current through sodium chloride solution.
shaalaa.com
  Is there an error in this question or solution?
Chapter 2: Physical and Chemical Changes - Exercise

APPEARS IN

S.P. Singh Concise Chemistry [English] Class 7 ICSE
Chapter 2 Physical and Chemical Changes
Exercise | Q 9

RELATED QUESTIONS

 Write short answer.

Name two reversible changes.


State whether the following is physical or chemical changes.

(energy produced) dissolving sugar in water —


Two chemical substances X and Y combine together to form a product P which contains both X and Y X + Y 􀁯 P
X and Y cannot be broken down into simpler substances by simple chemical reactions. Which of the following  statements concerning X, Y and P are correct ?

  1. P is a compound
  2. X and Y are compounds
  3. X and Y are elements
  4. P has a fixed composition

Distinguish between the following.

Physical change and chemical change


Read the paragraph and note down the various types of changes it mentions.
It was nearing six o'clock in the evening. The sun was setting. A breeze was blowing. Leaves on the tree were shaking. Sahil was sitting in the courtyard, rolling balls of wet soil, and shaping them into various toys. Then he felt hungry and went into the house. Mother made a dough from wheat flour and fried purees. While eating hot purees, his attention was drawn outside the window. It had started raining. There was lightning, too. Sahil was enjoying his dinner in the dim light.


Differentiate between a physical change and a chemical change with reference to – Nature of change is temporary and reversible or permanent and irreversible.


Differentiate between a physical change and a chemical change with reference to – Formation of products.


Select the chemical changes from the following list of changes

The carbon cycle.


Physical Change: Boiling::Chemical Change: ______.


Cutting a log of wood into pieces is a chemical change.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×