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What is the difference between a nuclear reaction and a chemical one?

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What is the difference between a nuclear reaction and a chemical one?

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In 1932, discovered a 3rd subatomic partice, the neutron.

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(1871– 1937)
In 1911, concluded that the atom contained a nucleus.

In 1919, discovered the next subatomic particle, the proton.

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(1868 – 1953)
In 1909, determined the charge of an electron.

Calculated the mass of a single electron.

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(1856 – 1940)

Cathode Ray Tube experiments

Late 1890’s identified the first subatomic particle – the electron.

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(1766- 1844)
Revised Democritus’s ideas

Experiments verified his theory
All matter is composed of extremely small particles called atoms.

All atoms of a given element are identical, having the same size, mass, and chemical properties.
Atoms of a specific element are different from any other element.

Atoms cannot be created, divided into smaller pieces or destroyed.

In a reaction, atoms are separated, combined, or rearranged.

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Greek phliosopher(460 - 370 B.C.)
Question: What holds atoms together?
First person to propose the idea that matter was not infinitely divisible.
Matter was made of tiny individual particles called atoms.
Matter is composed of empty space through which atoms move.
Atoms are solid, homogeneous, indestructible, and indivisible.
Different kinds of atoms have different sizes and shapes.
Differing properties of matter are caused by size, shape, and movement of atoms.
Apparent changes in matter caused by changes in the grouping of atoms.