Advertisements
Advertisements
प्रश्न
Fill in the blank.
When a candle burns, wax melts. Melting of wax is a ________ change.
Advertisements
उत्तर
When a candle burns, wax melts. Melting of wax is a physical change.
APPEARS IN
संबंधित प्रश्न
What is a chemical change ? Give two examples of chemical changes.
Classify the following as a physical or a chemical change.
Burning of paper
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.
State what is meant by the term – interconversion of matter. Is interconversion of matter a physical change or a chemical change.
Potassium chloride is added to water and stirred. A salt solution is obtained, which is then boiled, leaving behind a residue.
- Is the above change physical or chemical?
- Name the residue which remains behind after the salt solution is boiled.
- Is the change reversible or not reversible?
- Are the composition and properties of the original substance altered?
- Give a reason why the above experimentation would not be possible if calcium carbonate was taken in place of potassium chloride.
Select the correct answer from the choice given below to complete the sentence
The dissolution of lead nitrate in water is deemed as a _________ change.
State which of the following 1 to 5 pertain to – A: Physical Change B: Chemical change :
- Sublimation.
- Fermentation.
- Liquefaction or condensation.
- Magnetization.
- Respiration.
Name the following.
The gaseous product of the chemical change which takes place during respiration in living organisms.
Assertion: The explosion of fire cracker is a physical change.
Reason: A physical change is a reversible change.
Ice, water and water vapour look different and display different ______ properties but they are ______ the same.
