Does a blue litmus paper, turned red when dipped in an acidic solution, turn back to blue when dipped in a basic solution?
No it does not.
Change in colour of the litmus paper is a irreversible chemical change.
When a red litmus paper is dipped in the aqueous solution of X there is no change in colour. When a blue litmus paper is dipped in the same solution it turns red. Which among the following options can be the chemical X?
When a blue litmus paper is put in an acidic Solution, it turns red. Can the red litmus which has been formed used to indicate basicity?
In other words, can litmus paper which has changed its colour once be reused?
What happens when [5 MARKS]
a) A red litmus paper is dipped in a solution of calcium hydroxide.
b) A red litmus paper is dipped in a solution of sodium chloride.
c) A blue litmus paper is dipped in lemon juice.
d) A red litmus paper is dipped in distilled water.
e) A solution of sodium hydroxide is added to turmeric.
A student prepared 20% sodium hydroxide solution in a beaker to study saponification reaction. Some observations related to this are given below: (I) Sodium hydroxide solution turns red litmus blue (II) Sodium hydroxide readily dissolves in water (III) The beaker containing solution appears cold when touched from outside (IV) The blue litmus paper turns red when dipped into the solution The correct observations are :