Difference Between Metal and Heavy Metal

The key difference between metal and heavy metal is that heavy metals have relatively very high densities, atomic weights or atomic numbers compared to other metals.

Metals are materials that have a lustrous appearance and conducts electricity and heat relatively well. Compared to nonmetals and metalloids, metals have a high density, high thermal and electrical conductivity, large atomic numbers, etc. However, heavy metals are a type of metals that have very high densities, atomic numbers, and weights.

CONTENTS

1. Overview and Key Difference
2. What is Metal 
3. What is Heavy Metal
4. Side by Side Comparison – Metal vs Heavy Metal in Tabular Form
5. Summary

What is Metal?

A metal is a material that has a very lustrous appearance when polished, fractured or freshly prepared and has a high thermal and electrical conductivity. We have been using the metals for a very long time. Gold and copper were the first metals to be discovered. People used these metals to make tools, jewellery, statues, etc. At present, around 95 different types of metals have been discovered.

Metals are very important because of their unique characteristics. They are generally hard and strong (there are exceptions to this such as sodium. Sodium can be cut by a knife). Mercury is the metal which is in the liquid state. Except for mercury, all the other metals occur in the solid state. In comparison to other nonmetal elements, it is hard to break the metals or change their shape. Moreover, these materials have a shiny appearance, and most of them have a silvery shine (except gold and copper). Since some metals are very reactive with atmospheric gases like oxygen, they tend to get dull colours over time. It is mainly due to the formation of metal oxide layers. However, metals like gold and platinum are very stable and unreactive. Usually, metals are malleable and ductile, which allows them to be used for making certain tools.

Metallic Bonding

Furthermore, metals are atoms, which can form cations by removing electrons. Therefore, they are electropositive. We call the type of bond that forms between these atoms as metallic bonding. In these bonds, the material release electrons from their outer shells and these electrons get dispersed between metal cations. Therefore, they are known as a sea of delocalized electrons. We call the electrostatic interactions between the electrons and cations as “metallic bond”. The electrons can move; therefore, metals have the ability to conduct electricity. Moreover, they are good thermal conductors. Due to metallic bonding, metals have an ordered structure as well. High melting points and boiling points of these materials are also due to this strong metallic bonding.

What is Heavy Metal?

Heavy metals are a type of metals that have comparatively very high densities, atomic numbers, thermal and electrical conductivities, etc. Heavy metals may include metals or metalloids. These include transition metals, actinides, and lanthanides. Some examples include antimony, arsenic, bismuth, cadmium, cerium, chromium, cobalt, copper, gallium, gold, iron, lead, manganese, mercury, nickel, platinum, silver, tellurium, thallium, tin, uranium, vanadium, and zinc.

Heavy metals are especially known for their toxicity. In our environment, small amounts of these elements are present. Also, it is necessary to have a certain amount of heavy metals in our diet in order to maintain good health. However, large concentrations of heavy metal cause toxicity and can cause a lot of damages to living organisms. For example, it can cause reduced mental activity or damage it.

Furthermore, it can damage the lungs, kidneys, liver and other important organs. Heavy metals tend to accumulate in living organisms over food chains. We call this “bioaccumulation”. Therefore, it is important to know the sources of heavy metals and control their release to the natural environment.

What is the Difference Between Metal and Heavy Metal?

A metal is a material that has a very lustrous appearance when polished, fractured or freshly prepared and has a high thermal and electrical conductivity. Heavy metals are a type of metals that have comparatively very high densities, atomic numbers, thermal and electrical conductivities, etc. Hence, the key difference between metal and heavy metal is that heavy metals have relatively very high densities, atomic weights or atomic numbers compared to other metals.

Toxicity is another major difference between metal and heavy metal. Some metals can be toxic while others are not, but heavy metals can be toxic when present in higher concentrations. Moreover, metals do not bioaccumulate easily, but heavy metals do.

Summary – Metal vs Heavy Metal

Some metals are heavy metals. The key difference between metal and heavy metal is that heavy metals have relatively very high densities, atomic weights or atomic numbers compared to other metals. Other than that, heavy metals are toxic compared to other metals and can get bioaccumulated easily.

Reference:

1. Helmenstine, Anne Marie. “Metals: List of Elements.” ThoughtCo, Dec. 6, 2018, Available here.
2. Helmenstine, Anne Marie. “Heavy Metal Definition and List.” ThoughtCo, Sep. 29, 2018, Available here.

Image Courtesy:

1. “Periodic-Table-Metals” By CHEM1902 Main Group Chemistry –  (CC BY-SA 4.0) via Commons Wikimedia
2. “1130971” (CC0) via Pixabay 
3. “Bismuth crystal macro” By Dschwen – Own work (CC BY 2.5) via Commons Wikimedia