Are Gold Bars Flexible? (An Accurate Scientific Justification)

As an element, gold can be identified by its chemical symbol, Au, and its atomic number, 79. It is a transition metal element found in group 11 of the periodic chart. It can be found in nature both as a free element and in minerals with other elements.

Gold is an inert metal since it is one of the least reactive elements. It’s used to make jewellery and other high-priced items since it’s uncommon, beautiful, and precious. Gold was also commonly used for coinage in the past.

Have you ever seen gold foil that was really thin and wondered how it was made? To tell you the truth!

Are gold coins easily shaped? Gold, in fact, may be shaped in many different ways. As a matter of fact, gold is the most malleable metal there is. Metals that can be flattened out with a hammer are said to be malleable. For metals, this is because their atomic lattice structure allows for plastic deformation, in which the entire structure may be redesigned to achieve new geometries.

When something is malleable, it can be moulded by mechanical techniques such as hammering, beating, etc.

The malleability of gold begs the question: why?

Metals are malleable if they can be deformed plastically when subjected to modest stresses, like those produced by hammering.

Unlike many other elements, metals can be easily deformed when subjected to compression and strain.

Since this is the case, the metals can be pressed into sheets. By “most malleable,” we mean that gold can be beaten into the thinnest sheets of any metal.

Gold may be rolled out to a sheet one metre broad from just one gramme. Sheets can be made so thin that they are almost see-through.

The internal lattice structure of any metal, even gold, is what makes it so malleable. Gold’s atoms form a face-centered cubic lattice.

Layers of atoms are placed one on top of another to form a solid structure. With no connection between them, the layers can simply glide over one another under pressure. More and more layers become linearly ordered under increased pressure, leading to the formation of thinner and thinner sheets.

Thus, the behaviour of gold to be shaped into various objects is due to its atomic organisation. Gold’s great malleability is one of the factors contributing to its high price.

The Influence of Environmental Conditions on Gold’s Sculptability

The ductility of metals, particularly gold in this example, can be attributed to a number of variables.

But the two most crucial components that are accountable for gold’s malleability are:

• Bonding of metals

In the preceding paragraph, we discussed how the atoms within metals tend to settle in layers one on top of the other. Plastic deformation of metals is made possible by the ability of its layers to roll over one another.

However, one would question how, under normal circumstances, these layers could possibly hold together. True, metallic bonding holds these layers together.

As its name suggests, metallic bonding is unique to metals in which one or more valence electrons are free to move about the atom. These electrons are no longer bound to a specific atom, but rather they are free to move around the local area under the collective jurisdiction of all the atoms around them.

Layers of atoms can slide past each other despite being bonded together because the metallic bonding is a relatively weak force keeping the atoms together due to the mobility of the electrons.

All metals are malleable and ductile because of their metallic connection, which allows them to be easily moulded.

Let’s break it down with some numbers:

The accompanying diagram shows the typical atomic layering within of gold. However, as seen in the image below, when an external force or pressure is applied, the various layers roll or glide over each other.

You have gained an understanding of the significance of metallic bonding and how it impacts malleability.

• Weather conditions

When a metal is heated, its atoms gain kinetic energy and, as a result, they migrate farther apart. If an external force is provided with the same goal of spreading these atoms apart, the process becomes simpler.

This is why higher temperatures cause metals to soften and become ductile. If you’ve ever watched metal being reshaped or moulded, you know that the material is heated to well above its melting point.

Metals also suffer from the effects of the rising temperature. In other words, when the temperature drops below a particular point, metals will become brittle. The temperature at which this occurs is referred to as the transition temperature, and the effect is known as the embrittling effect.

Over and above the transition temperature, metals are pliable, while below it they become brittle.

The relationship between metals’ temperature and their malleability and ductility is graphically represented in the following figure.

The accompanying graph, known as the impact transition curve, is a useful tool for understanding the effect of temperature on the malleability of metals.

Temperature has been shown to increase the malleability of a material up to a certain point, after which it remains constant, and the same is true for brittleness.

In general, the transition temperature is a function of the metal’s purity and other factors.

What Gold Looks Like Inside Its Lattice Structure

It is commonly accepted that a given element’s lattice structure consists of two distinct components: the Bravais lattice and the atoms that make it up. An element’s atoms occupy a region called a Bravais lattice, which is itself divided into cells that make up the element’s atomic structure.

Assuming a cube for a unit cell, atoms inside can be organised in a variety of distinct arrangements, each of which has its own name.

In gold, the atoms form a lattice with a face-centered cubic (FCC) structure. A cube, representing gold, can be used to describe this configuration.

Now, the gold atoms are situated inside the cube with one atom on each of the six faces and one atom at each of the eight corners (also called lattice points) (that is why the name, face-centered).

As shown below, gold has the following FCC structure.

The number of atoms in a unit cell can be calculated by:

A unit cell’s corners account for one eighth of the atoms in the cell.

Additionally, there are 8 vertices. So, 8 times 1/8th is one atom.

Now, half of the unit cell’s atoms come from the cube’s face or sides.

Six faces times one-half is three atoms, since the cube has six sides.

Therefore, there are 1, 3, or 4 gold atoms in a single gold molecule.

the relative malleability of certain metals

Metals’ malleability is the ability to undergo plastic deformation without cracking, thus they can be shaped in several ways.

All metals can be shaped in a variety of ways, as we’ve shown. However, other parameters, including lattice structure, atomic size, the quantity of valence electrons, etc., determine the degree of malleability.

More electrons will be accessible for metallic bonding if the atoms are big enough to increase their distance from the nucleus. The bonding between atoms within metals is also affected by the valence electrons.

The malleability of metals can be ranked from most malleable to least malleable based on a number of parameters, including those listed below.

Gold’s unique qualities

Here are just a few of gold’s many useful characteristics:

Yellow gold (atomic number 79) has a high refractive index and a high specific gravity, making it ideal for use in electronics.

Gold has a boiling temperature of 2700 °C and a melting point of 1064 °C.

For its high thermal and electrical conductivity, copper is employed in a wide range of electrical components.

Gold is used to coat astronauts’ helmets because it reflects heat and light very well.

Gold’s appealing bright glittering appearance makes it ideal for manufacturing jewellery and other expensive ornamental goods, driving up its demand.

If you’re curious about how Gold can be shaped, here’s a cool video to watch.

Conclusion

Metals that can be hammered into thin sheets have a malleable quality.

The malleability of metals can be traced back to the specific way their atoms are arranged within the metal. Metals can take on a wide range of forms because of their malleability.

Gold’s atoms are organised in a face-centered cubic lattice, making it the most malleable metal.

Gold is composed of atomic layers that can glide past one another under pressure.

Gold, like other metals, is affected most by temperature and metallic bonding in terms of its malleability.

To Sum It Up: Have Fun Studying!

Read more: Forces Between CH4 Molecules

Misha Khatri
Misha Khatri is an emeritus professor in the University of Notre Dame's Department of Chemistry and Biochemistry. He graduated from Northern Illinois University with a BSc in Chemistry and Mathematics and a PhD in Physical Analytical Chemistry from the University of Utah.

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