Chapter 6, Problem 25Q

(a)

Interpretation Introduction

Interpretation:

In the conversion of base metals into the precious metals chemists could they never succeed reason for this has to be given.

Explanation of Solution

Given statement,

In the conversion of base metals into the precious metals chemists could they never succeed.

Alchemists were perhaps the first practical chemists, but they didn’t have the advantage of knowing anything about atomic structure or nuclear reactions. No chemical reaction can give gold from another element; a nuclear reaction is required. Even if they had envisioned a nuclear reaction that would produce gold from another isotope, they clearly did not have the means to accomplish this.

(b)

Interpretation Introduction

Interpretation:

Conversion of possibility of lead or mercury into gold has to be given.

Explanation of Solution

Today we can convert lead or mercury into gold. Nuclear reactions are given below for this conversion.

Reactions for the conversion of lead into gold,

$\begin{array}{l}{\text{Al}}^{\text{27}}\text{+}{\text{Pb}}^{\text{204}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}{\text{He}}^{\text{4}}\text{+}\text{3}{\text{H}}^{\text{1}}\\ {\text{Al}}^{\text{27}}\text{+}{\text{Pb}}^{\text{206}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}\text{2}{\text{He}}^{\text{4}}\text{+}\text{3}{\text{H}}^{\text{1}}\\ {\text{Al}}^{\text{27}}\text{+}{\text{Pb}}^{\text{207}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}\text{2}{\text{He}}^{\text{4}}\text{+}\text{2}{\text{H}}^{\text{1}}\\ {\text{Al}}^{\text{27}}\text{+}{\text{Pb}}^{\text{208}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}\text{2}{\text{He}}^{\text{4}}\text{+}\text{3}{\text{H}}^{\text{1}}\end{array}$

Reactions for the conversion of mercury into gold,

$\begin{array}{l}{\text{Al}}^{\text{27}}\text{+}{\text{Hg}}^{\text{198}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}{\text{H}}^{\text{1}}\\ {\text{Al}}^{\text{27}}\text{+}{\text{Hg}}^{\text{199}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}\text{2}{\text{H}}^{\text{1}}\\ {\text{Al}}^{\text{27}}\text{+}{\text{Hg}}^{\text{200}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}\text{3}{\text{H}}^{\text{1}}\\ {\text{Al}}^{\text{27}}\text{+}{\text{Hg}}^{\text{201}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}{\text{He}}^{\text{4}}\\ {\text{Al}}^{\text{27}}\text{+}{\text{Hg}}^{\text{202}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}{\text{He}}^{\text{4}}\text{+}{\text{H}}^{\text{1}}\\ {\text{Al}}^{\text{27}}\text{+}{\text{Hg}}^{\text{204}}\stackrel{}{\to }{\text{Al}}^{\text{27}}\text{+}{\text{Au}}^{\text{197}}\text{+}{\text{He}}^{\text{4}}\text{+}\text{3}{\text{H}}^{\text{1}}\end{array}$

(c)

Interpretation Introduction

Interpretation:

Whether nuclear reactions can be used to produce consumer quantities of precious metals or not this has to be given.

Explanation of Solution

To synthesize gold in consumer quantities:

• A nuclear reactor has to be built to act as a source of neutrons.
• By using mercury as starting material and large amount of work, only a very small portion of gold is created.
• Decontamination of the created gold is harder than it sounds because the separation of non-radioactive gold from radioactive gold is not possible by using purely chemical methods.