A stain of curry on a white cloth become reddish brown when soap is used because the soap is:
Basic in nature
Curry Stain Chemistry: Soap’s Effect
The color change observed when soap interacts with a curry stain on white cloth is due to the chemical properties of the ingredients involved.
Understanding the Color Change
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Indicator Property: Curry stains often contain turmeric, a natural compound that acts as a pH indicator. Turmeric is typically yellow in color.
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pH and Color Variation: Turmeric exhibits different colors depending on the acidity or alkalinity (pH) of its environment. It appears yellow in neutral or acidic conditions but changes to a reddish-brown hue in basic (alkaline) conditions.
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Nature of Soap: Soaps are generally manufactured using alkaline substances (like sodium hydroxide) and are therefore basic in nature.
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Reaction: When soap, being basic, comes into contact with the turmeric in the curry stain, it alters the pH. This shift to a basic environment causes the turmeric indicator to change its color from yellow to reddish-brown.
Therefore, the soap is basic in nature, causing the color change.
Important Questions from Equilibrium
What is the pH of a solution prepared by dissolving $0.0025$ moles of $HNO_3$ in $250\,mL$ of water?
Which species acts as acid like behaviour in the following reaction?
\(HPO_4^{2-}+NH_4^{1+}\rightarrow H_2PO_4^{1-}+NH_3\)
Aqueous solution of CH 3COONa is:
pH of a neutral solution is ___________.
For the reaction N 2(g) + 3H 2(g) \(\rightleftharpoons\) 2NH 3(g) ΔH = -ve :
