What is defined as the plants and animals and the physical surroundings, including the sun, air, soil, and water? 1.population
2.organism
3.ecosystem
4.community

ecosystem

Explanation:

because population isnt it neither community or orgamism

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