Chemical Changes
Chemical Changes: Overview
This topic covers concepts, such as, Test of Carbon Dioxide Gas, Chemical Changes, Ozone Layer Depletion & Ozone Layer etc.
Important Questions on Chemical Changes
Curd, lemon juice, orange juice and vinegar. Identify them whether they are basic or acidic.
_____ turns blue litmus red.
Which of the following bases completely dissociates into ions when dissolved in water?
Differentiate between strong and weak bases.
A basic solution is an aqueous solution containing more _____ ions than hydrogen (H+) ions.
What do you mean by basic solution?
Burning of coal is a physical change.
Why burning of coal is considered as irreversible change?
Why burning of fuels is classified as chemical change?
Litmus is obtained from _____.
Where else have you seen chemical reaction?
| Where have you seen chemical reaction? | What were the changes due to the reaction? Mention change of colour and any other changes. | What was the result of such a reaction? |
Calcium oxide reacts with water to form calcium hydroxide along with the evolution of heat is an example of _____ reaction.
Two non-metals react sometimes explosively when brought in close contact.
The silver residue obtained on heating mercury (II) oxide is mercury. This is an example of a decomposition reaction.
On heating green copper carbonate changes to _____ copper oxide. (black/yellow)
