What would happen if Earth didn't have any iron?

Question

I'm writing a paper about iron for chemistry class, and among the "guide" questions is how the metal can be connected to society and how it would look without it, but I can't find anything interesting.

I'm not very educated in the subject, so I'm wondering what it would be like without any iron whatsoever. How would technology have developed? Could we build skyscrapers without it? Would Earths reduced mass and gravitational force cause the atmosphere to disappear? etc.

Anything at all would be helpful

Answer 1

We would not have evolved at all. In fact life would probably not have evolved on the Earth. Without iron at the Earth's core, there would be no magnetic field. Without a magnetic field, the sun would have blown away the atmosphere over 3 billion years ago. But assuming it didn't by some miracle, life wouldn't have evolved; at least not in any form we'd recognize. The initial conditions for life to emerge were something like this: Poisonous methane/CO2/nitrogen/SO2 atmosphere, extreme volcanic activity, far high than today's average background radioactivity, and iron saturated oceans. Following the late heavy bombardment, the ocean has trillions of metric tonnes of iron dissolved in it. This dissolved iron probably played a role in the complex chemistry that created the first self replicating carbon-based molecules. I'm not an organic chemist, so I don't really know the specifics. It was only after oxygen producing cyanobacteria evolved that the iron was rusted out of solution and precipitated to the sea floor. These iron deposits formed the great iron ranges.

Answer 2

As far as skyscrapers go, masonry was used before the skeletal steel skyscraper was developed, so look at the tallest masonry structures in New York City and you'll see the limits of non-steel construction. The problem is that the walls at the base have to become increasingly thick to support the superstructure, until a point is reached that there is virtually no usable floor space remaining, and that's the limit.

.

flyingtiggeruk and ET already addressed the hemoglobin problem. There *are* living creatures with copper-based blood, so we at least know that's possible, as opposed to contemplating life without carbon, which may well not be.

.

I remember Jack Vance wrote a pair of novels based on the premise of a metal-poor world where even an iron coin was worth a fortune, named "Big Planet" and "Showboat World", that address the challenges faced by a civilization challenged by no metal resources. I see Amazon has a Kindle version for $4.61. It may not directly address your question but might stimulate your thinking on the topic, and is an easy read.

.

.

Answer 3

Whole-Earth implications. Smaller, less gravity, no magnetic field.



Geological implications. Rocks would be different, more "felsic" in geological terms. There might be no distinct continental and oceanic crust, and that would mean no deep oceans. Possibly a geology more like Venus, where the entire surface gets replaced every few hundred million years in an episode of massive vulcanism.



Biological implications. Hemoglobin wouldn't work, lots of other biological molecules would have to be changed for alternatives.



Ancient historical implications. No iron weaponry. In Europe bronze became somewhat expensive, and the invention of iron smelting enabled much cheaper weapons and tools. Without that history would have taken a very different path.



Recent historical implications. The Industrial Revolution would be very different. Perhaps it would have happened in Asia or America, where ores of other metals were more available in contrast to Europe where they had been depleted. Perhaps it would have happened later, after developments in chemistry and electricity made the use of metals like aluminium economical.



Really, Earth as we know it could not exist.

Answer 4

The fundamental answers about the Earth's core, hemoglobin and others are very interesting and very important. On a more macro level I've heard it said that steel has become the most common substance on Earth. Look up Henry Bessemer - before him, steel was relatively rare and quite expensive. His invention is little known to the general public, but it changed the course of human history.

Answer 5

Well... there may not be any 'Earth'... Iron is a key component of our core, and makes up about 35% of Earth's mass. Without the iron/nickel outer core, there'd be no magnetic field protecting the surface from solar radiation - which may prevent life from ever forming.

Answer 6

The first technological metal was copper, which can be found in nature in its elemental form. But copper is very soft, and not useful for much. When copper was alloyed with tin to make bronze, it became much stronger and thus much more useful, and then founded the "Bronze Age". But the very best metal was observed to fall from the sky/heavens, in the form of Iron meteorites. It was the "Metal of the Gods", far stronger than copper or bronze. Copper was observed to corrode into a greenish oxide, and Iron likewise rusted to red, or orange. Copper was then observed to be smeltable from greenish rocks. Could Iron be smelted from reddish rocks? The Hittites of what is now central Turkey first figured this out, and for many decades, their iron/steel weapons were nearly invincible. But as with all military secrets, the word eventually leaked.............and the rest is history.

Answer 7

There would be no haemaglobin in blood so it's unlikely that there would be any mammals on the planet so we wouldn't be here.



There would be no earth magnetic field so there would be nothing to repel the EM radiation from the sun so a lot of other life probably wouldn't exist.



If you discount all that, steel is used in many different places from hypodermic needles to aircraft to ships to buildings.

Answer 8

Copper based blood - lower energy animals. Copper and aluminium would stand in for Iron.

Lack of magnetic field would have a tiny effect - Alpha and Beta radiation is stopped by a meter of air and Gamma is not deflected by the magnetic field.

Alloys would stand in for steel - hypodermics were bronze at first.

Answer 9

We would not exist ... and I doubt any life would have formed. Iron is at the core of the planet and produces the magnetic field which redirects deadly cosmic rays away from Earth.

Answer 10

Hmm, no steel, that leaves out a lot. What doesn't have steel or stainless steel? Mind you aluminum and brass/bronze/ copper are alternatives.

Answer 11

your blood would be colorless and you couldn't breathe.

Answer 12

we would not exist - we need iron in our blood

Answer 13

re