Question 2 :
When baking soda is mixed with lemon juice, bubbles are formed with the evolution of a gas. What type of change is it?
Question 4 :
Which of the following is true when milk changes into curd?
Question 5 :
Which of the following methods are used to prevent rusting in iron?
Question 7 :
During galvanisation, iron is coated with _____ to prevent it from rusting.
Question 9 :
Which of the following is a correct example of a chemical change .
Question 10 :
Can you reverse back the process of rusting by some simple method?
Question 13 :
Which of the following matches the best with sugar candy (mishri)?
Question 14 :
Which one is an example of a chemical reaction where sound is produced ?
Question 15 :
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. Which type of changes will he observe, physical or chemical?
Question 17 :
The gas we use in the kitchen is called liquefied petroleum gas (LPG). In the cylinder it exists as a liquid. When it comes out from the cylinder it becomes a gas (Change-A) then it burns (Change-B). The following statements pertain to these changes. Choose the correct one.
Question 18 :
Which of the following is an example where physical change is reversible in nature ?
Question 19 :
State true or false: Condensation of steam is not a chemical change.
Question 20 :
A change in which only the physical properties af any substance get changed and no new substance is formed is called as.
Question 21 :
Ships suffer a lot of damage though they are painted. Is this statement true or false?
Question 22 :
Dissolving sugar into hot water is an example of ______ solution.
Question 23 :
Melting of wax is a change where a _____ changes to _____ state.
Question 24 :
Anaerobic bacteria digest animal waste and produce biogas (Change-A). The biogas is then burnt as fuel (Change-B). The following statements pertain to these changes.Choose the correct one.
Question 25 :
State true or false: Burning of wood is the chemical change.
Question 28 :
A change in which the composition and chemcal properties of the substance get changed is called as.
Question 29 :
When a candle burns, both physical and chemical changes take place. Is this statement true or false?
Question 31 :
Paheli’s mother made a concentrated sugar syrup by dissolving sugar in hot water. On cooling, crystals of sugar got separated. Which type of change does it indicate?
Question 32 :
State true or false: Iron pipes coated with zinc do not get rusted easily.
Question 33 :
Can you reverse back the process of rusting by some simple method?
Question 36 :
Which one is an example of a chemical reaction where sound is produced ?
Question 37 :
A change in which the composition and chemcal properties of the substance get changed is called as.
Question 40 :
If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust . Is rust different from iron?
Question 41 :
State true or false: Iron and rust are the same substances.
Question 43 :
Dissolving sugar into hot water is an example of ______ solution.
Question 44 :
Which of the following is a correct example of a chemical change .
Question 45 :
When a candle burns, both physical and chemical changes take place. Is this statement true or false?
Question 46 :
Cutting of a log of wood into pieces is which type of change?
Question 48 :
Cutting of a log of wood into pieces is which type of change?
