You are here
Q2 (Medium): You are provided with three unknown solutions labelled A, B, and C, but you do not know which of these are acidic, basic, or neutral. Upon adding a few drops of red litmus solution to solution A, it turns blue. When a few drops of turmeric solution are added to solution B, it turns red. Finally, after adding a few drops of red rose extract to solution C, it turns green. Based on the observations, which of the following is the correct sequence for the nature of solutions A, B, and C?
Answer:
We have studied that different
indicators
show
specific colours
in
acidic
and
basic
solutions. This is why we can identify each solution.
- Solution A - turns red litmus blue (basic)
- Solution B - turns turmeric red (basic)
- Solution C - turns red rose green (basic)
- Sequence : A-Basic, B-Basic, C-Basic
Q4 (Medium): A liquid sample from the laboratory was tested using various indicators: Red litmus - No change; Blue litmus - Turned red; Turmeric - No change. Based on the tests, identify the acidic or basic nature of the liquid and justify your answer.
Answer:
We have studied that
acidic substances
turn
blue litmus red
and show
no change
with
red litmus
and
turmeric
. This is why the liquid is acidic.
- Blue litmus turns red - indicates acid
- Red litmus shows no change - confirms acid
- Turmeric shows no change - confirms acid
- All tests point to acidic nature
Q7 (Medium): Grape juice was mixed with red rose extract; the mixture got a tint of red colour. What will happen if baking soda is added to this mixture? Justify your answer.
Answer:
We have studied that
grape juice
is
acidic
and
baking soda
is
basic
, causing
neutralisation reactions
. This is why the colour will change.
- Red colour shows acidic grape juice
- Baking soda is basic substance
- Neutralisation occurs when acid meets base
- Red colour changes to green colour
Q11 (Medium): The extract of red rose turns the liquid X to green. What will the nature of liquid X be? What will happen when excess of amla juice is added to liquid X?
Answer:
We have studied that
red rose extract
turns
green
in
basic solutions
and
amla juice
is
acidic
. This is why neutralisation will occur.
- Green colour indicates liquid X is basic
- Amla juice is acidic in nature
- Acid + base causes neutralisation reaction
- Green colour changes to red colour
