A solution is prepared in which 0.00100 mol Ni(NO3)2 and 0.500 mol NH3 are dissolved in a total volume of 1.00 L. What is the concentration of Ni(H2O)6 21 ions in the solution at equilibrium?

Respuesta :

Explanation:

The given reaction will be as follows.

     [tex]Ni^{2+} + 6NH_{3} \rightarrow Ni(NH_{3})^{2+}_{6} + 6H_{2}O \rightarrow Ni(H_{2}O)^{2+}_{6} + 6NH_{3}[/tex]

As [tex]NO^{2-}_{3}[/tex] are the separator ions. Hence, molarity of [tex](NO_{3})_{2}[/tex] will be calculated as follows.

            Molarity of [tex](NO_{3})_{2}[/tex] = [tex]\frac{no. of moles of Ni^{2+}}{volume in liter}[/tex]

                                          = [tex]\frac{0.001}{1}[/tex] = 0.001 M

             Molarity of [tex]NH_{3}[/tex] = [tex]\frac{no. of moles of NH_{3}}{volume in liter}[/tex]

                                         = [tex]\frac{0.5}{1}[/tex] = 0.5 M

Hence, the molar ratio of [tex]Ni(NO_{3})_{2}[/tex] and [tex]NH_{3}[/tex] is [tex]\frac{1}{6}[/tex].

So, it means that 0.001 moles of [tex](NO_{3})_{2}[/tex] will require 0.001 × 6 = 0.006 moles of [tex]NH_{3}[/tex].

But in actual we are given that there are 0.5 mol of [tex]NH_{3}[/tex].

As molar ratio of [tex](NO_{3})_{2}[/tex] and [tex]Ni(H_{2}O)^{2+}_{6}[/tex] is 1:1.

Therefore, concentration of [tex]Ni(H_{2}O)^{2+}_{6}[/tex] will be calculated as follows.

             Concentration of [tex]Ni(H_{2}O)^{2+}_{6}[/tex] = [tex]\frac{/text{no. of moles of [tex]Ni(H_{2}O)^{2+}_{6}}[/tex]}{/text{volume in liter}}[/tex]

                                           = [tex]\frac{0.001}{1}[/tex]

                                           = 0.001 M

Thus, we can conclude that the concentration of [tex]Ni(H_{2}O)^{2+}_{6}[/tex] ions in the solution at equilibrium is 0.001 M.