Which of the following equations describes a single-replacement reaction?

a. 2n2o5 (g) = o2 (g) + 4no2 (g)
b. 2na (s) + cl2 (g) = 2nacl (s)
c. cl2 (g) + 2kl (s) = 2kcl (s) + l2 (g)
d. h2 (g) + br2 (g) = 2hbr (g)

Option (C) is the correct answer.

Explanation:

A chemical reaction in which more reactive metal or substance displaces one less reactive metal or substance then this type of reaction is known as single displacement reaction.

Thus, we can conclude that out of the given options, the reaction equation            

As in this reaction, one chlorine atom replaces one iodine atom hence it is a single displacement reaction.

the ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (uvr) from the sun, protecting life on earth from its potentially harmful effects. when the sky is clear, there is an inverse relationship between stratospheric ozone and solar uvr measured at the earth's surface.

the answer is 1 i believe