Solved: Determine whether HI can dissolve each metal

Problem 107E

Determine whether HI can dissolve each metal sample. If it can, write a balanced chemical reaction showing how the metal dissolves in HI and determine the minimum volume of 3.5 M HI required to completely dissolve the sample.

a. 2.15 gAl

b. 4.85 gCu

c. 2.42 gAg

                                                              Step by step solution

Step 1 of 3

(a)

Most of the acids dissolve metals by the reduction of   ions to  hydrogen gas and corresponding oxidation of the metal to its ion.

The standard reduction potential of the    to  is 0 volts.

The metals which have below these reduction potential values can dissolve in acids.

The reduction potential value of “Ag” is -1.66 V. Hence, it is dissolved in the acid. The chemical reaction is as follows.

Let’s calculate the required moles of hydrogen iodide to dissolve the amount of aluminium .

From the given,

Mass of aluminium = 2.15 g

Concentration of HI = 3.5 M

Hence, the required moles of hydrogen iodide to dissolve the amount of aluminium is 0.239 mol.

Let’s calculate the volume of HI.

Therefore, the required volume of HI to dissolve a given amount of aluminium is 68.29 mL.