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.

aquifers are bounded above and below by impermeable rock. the driving force of groundwater movement in confined aquifers is pressure, rather than gravity.

the dissociation of nickel hydroxide is follows:

the concentration of hydroxide ion is

the equilibrium constant value of nickel hydroxide is = 6.1 * 10^-^1^6 and thus equilibrium equation can be written as:

thus, concentration of ni is 0.23 * 10^-^4 mol /l