How did we come up with the name "atomic bomb"?

Question

At first, my initiate question was: What is the difference between an atomic and a nuclear bomb?:

Nuclear bombs are of two types — those that depend on fission, like atomic bombs, and those that depend on fusion, like hydrogen bombs

Regardless of fission or fusion, both of them are reactions of subatomic particles, no reaction of atoms. Therefore, atomic bomb is a wrong name. Do you have any explanation for this? Why has atomic bomb instead of another better term become the predominant term?

Answer 1

I'm going to try to answer the question you end with, "Why has atomic bomb instead of another better term become the predominant term?", rather than the question in your title, because that's the historical question. (The other might be interesting to debate, but unlikely to produce a satisfying final answer.)

Let's start with the Google ngram, showing the relative frequency of atomic and nuclear in the period 1900 to 1940:

As you can see, atomic was much more common than nuclear throughout this period. Note that the Manhattan project didn't get started until 1942.

Next let's look at atomic bomb during the same period:

As you can see, the term was around for quite some time before the actual bomb.

At this point, we run out of hard data, but I can still offer some food for thought. First, the etymology of nuclear: its use in physics derives (around 1914) from its biological meaning. By contrast, atomic has had roughly the same meaning since the ancient Greeks (very roughly, but close enough for this topic).

I also searched through some of the novels of H.G. Wells. One stood out: The World Set Free, published in 1914. Richard Rhodes recounts in The Making of the Atomic Bomb that Wells's novel made a great impression on Leo Szilard when he read it in 1932, a few years before he discovered the nuclear chain reaction. This novel describes (in Szilard's summary):

...the liberation of atomic energy on a large scale for industrial purposes, the development of atomic bombs, and a world war .... in this war the major cities of the world are all destroyed by atomic bombs.

Wells uses the terms atomic energy and atomic bomb throughout. Where did he get these terms? Wells inscribes the book

TO Frederick Soddy's Interpretation Of Radium This Story, Which Owes Long Passages To the Eleventh Chapter Of That Book, Acknowledges And Inscribes Itself

Now, Soddy was Rutherford's student, and the two of them discovered that the thorium atom was not unsplittable: a piece (the alpha particle) splintered off during radioactive decay, energy being released as well. (True also for radium.) This work was done in 1900-1903. Rutherford's nuclear model of the atom came later: the Geiger-Marsden experiment in 1909, the model in 1911.

So here's a conjectural history of the terms atomic energy and atomic bomb:

1. Rutherford-Soddy make their discoveries and Soddy writes his book. The term nuclear is not used, since its use in physics is still in the future.
2. Wells reads Soddy's book and writes his own work of fiction, picking up on atomic.
3. Szilard reads Wells's book, and when he discovers the basic mechanism of the atomic bomb, he naturally perpetuates the term atomic.

As I said, conjecture. But we can be pretty sure that in the period 1910 to 1940 (roughly), nuclear was a fairly technical term, not in general use --- like atomic.

Answer 2

They really do involve atoms. . .

There are two types of nuclear weapons: fission bombs and fusion bombs. Fission bombs depend on - surprise! - nuclear fission, while fusion bombs depend on - wait for it - nuclear fusion. A good overview of the two can, of course, be found here and here. Just don't let the NSA catch you. . .

Actually, nuclear bombs do involve atoms. In fission bombs, these are generally uranium and plutonium, the scary elements you think about whenever you hear the word "nuclear." Here's how the reaction goes:

1. Stick a chunk of a material for the reaction (perhaps uranium, for simplicity).
2. Fire a neutron at it.
3. Let the (now unstable) uranium nucleus decay into other products, and emit free neutrons.
4. Repeat. Watch as a lot of energy is released, in the form of photons.

That's really how nuclear fission works. It does involve atoms, because it involves nuclei - in the form of atoms.

Answer 3

Yes, atomic bomb is a good name. And so is nuclear bomb.

There is no reason to make a distinction between the two, and this distinction doesn't exist in some languages, which tends to show it is not based on scientific facts but on English usage.

In French for exemple, we make a distinction between fission bomb (A-type) and fusion bomb (H-type), but both are called atomic/nuclear bombs.

In my opinion A-bomb are called atomic bombs because they were the first to be developed, and when the name was taken and people developed H-bombs they had to use a less generic name to make the distinction. H-bombs use A-bombs to start the reaction, so there is no explanation why a fusion bomb should be less atomic than a fission bomb.