Question

f. B. The bronze medals ar Cu and Zn Silver articles becomes black on prolonged exposure to air. This is due to formation of Ag₂0 iii. AgCN ii. Zn and Ni ii. iv. Ag₂S Ag₂O and Ag₂S​

Answer 1

iv. Ag₂O and Ag₂S.

Step-by-step explanation:

question basically asks

Why do silver things turn black after a long time? when silver reacts with sulfur and oxygen in the air, it creates silver sulfide which is the black tarnish

Silver articles become black on prolonged exposure to air due to the formation of silver sulfide (Ag₂S) and silver oxide (Ag₂O). This process is called tarnishing.

Silver is a very reactive metal and it reacts with sulfur compounds in the air to form silver sulfide. Silver sulfide is a black compound that gives tarnished silver its characteristic dark color. Silver can also react with oxygen in the air to form silver oxide. Silver oxide is a brown or yellow compound that can also contribute to the tarnishing of silver.

The other options are incorrect:

iii. AgCN is silver cyanide, which is a white compound that is used in electroplating.

ii. Zn and Ni are zinc and nickel, which are metals that are commonly used in alloys with silver. They do not form black compounds when exposed to air.

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