Silver jewelry gradually loses its shine because a thin black layer of silver sulphide, , forms on its surface.
Placing the silver object in boiled water with sodium bicarbonate and a piece of aluminum foil allows aluminum to remove sulphur from silver sulphide because aluminum is more reactive than silver.
Aluminum removes sulfur from silver sulphide, causing the silver surface to shine again.
1. What causes silver jewelry to develop a black surface layer over time?
2. Why does aluminum foil help restore the shine of tarnished silver in boiled water with sodium bicarbonate?
3. Which statement correctly distinguishes a cation from an anion?
Why does silver jewelry gradually lose its shine?
A thin black layer of silver sulphide forms on its surface.
How does aluminum remove sulphur from silver sulphide in boiled water?
Because aluminum is more reactive than silver.
What is a cation in chemistry?
A cation is a positive ion.
What does a universal indicator show about a solution?
It shows if a solution is acidic, alkaline, or neutral by color change.
Silver tarnish removal process - chemical
Aluminum reacts with silver sulfide, restores shine.
Universal indicator measures?
pH, acidity, alkalinity, neutral.
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