Understanding the Nucleus (2.1.3) Flashcards
Alpha particle
A high-energy helium nucleus emitted from a nucleus in alpha decay.
Bends slightly towards negative, positive charge, large mass/charge ratio, stopped by ___
Beta particle
A high-energy electron emitted from a nucleus in beta decay.
Bends slightly towards positive, negative charge, small mass/charge ratio, stopped by ___
Gamma radiation
High-energy electromagnetic radiation emitted in nuclear reactions; electromagnetic radiation with a wavelength shorter than 10^-11 m.
Travels linearly, neutral charge, no charge mass/charge ratio, stopped by ___
What is the Gold Foil Experiment?
An experiment devised by Ernest Rutherford, Hans Geiger, and Ernest Marsden. They shot alpha particles through gold foil and observed where they landed.
• Radioactivity provided scientists in the early part of the twentieth century with a new tool for examining the interior of the atom.
• Radioactivity provided scientists in the early part of the twentieth century with a new tool for examining the interior of the atom.
• Ernest Rutherford discovered the nucleus of the atom using a beam of α particles.
• Ernest Rutherford discovered the nucleus of the atom using a beam of α particles.
• James Chadwick used a beam of α particles to indirectly detect neutrons.
• James Chadwick used a beam of α particles to indirectly detect neutrons.
• Since atoms were found to be divisible, Dalton’s atomic theory of matter had to be revised.
• Since atoms were found to be divisible, Dalton’s atomic theory of matter had to be revised.
The discovery of subatomic particles required that
Dalton’s atomic theory of matter be revised.
All matter is composed of atoms, but atoms are
divisible into protons, neutrons, and electrons.
Each element has a characteristic nuclear charge
(number of protons). However, atoms of a given
element can have different numbers of neutrons,
and therefore different masses.
However, since chemical reactions do not involve
rearrangements of protons or neutrons, Dalton’s
atomic theory of matter still holds for chemical
reactions.
The discovery of subatomic particles required that
Dalton’s atomic theory of matter be revised.
All matter is composed of atoms, but atoms are
divisible into protons, neutrons, and electrons.
Each element has a characteristic nuclear charge
(number of protons). However, atoms of a given
element can have different numbers of neutrons,
and therefore different masses.
However, since chemical reactions do not involve
rearrangements of protons or neutrons, Dalton’s
atomic theory of matter still holds for chemical
reactions.
