Atomic Theory Answers

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Why did Thomson’s results from experimenting with cathode rays cause a big change in scientific thought about atoms?

A
His results gave people a picture of what atoms look like for the first time.
B
His results gave the first clues that atoms could be created and destroyed.
C
His results gave the first experimental evidence that matter is made up of atoms.
D
His results gave the first evidence that atoms were made up of smaller particles.
2
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Scientists have changed the model of the atom as they have gathered new evidence. One of the atomic models is shown below.

Question illustration
A
A few of the positive particles aimed at a gold foil seemed to bounce back.
B
The colors of light emitted from heated atoms had very specific energies.
C
Experiments with water vapor showed that elements combine in specific proportions.
D
Cathode rays were bent in the same way whenever a magnet was brought near them.
3

Which statement describes one feature of Rutherford’s model of the atom?

A
The atom is mostly empty space.
B
The atom cannot be divided into smaller particles.
C
Electron clouds are regions where electrons are likely to be found.
D
The electrons are located within the positive material of the nucleus.
4

The modern model of the atom describes electrons in a little less specific detail than earlier models did. Why is it that being less sure about the placement of electrons in an atom is actually an improvement over earlier models?

A
Electrons do not follow specific paths, so describing the area where an electron is likely to be is more scientifically accurate.
B
Electrons were thought to be negatively charged, but now scientists know that their charge depends on their energy level.
C
The modern model is based on mathematical equations, so the results become less clear when the decimals are rounded.
D
The position of electrons in atomic models has changed so much that it is better to have a less specific model than to be wrong again.
5

Which statement belongs to Dalton’s atomic theory?

A
Atoms have a massive, positively charged center.
B
Atoms cannot be created or destroyed.
C
Atoms can be broken down into smaller pieces.
D
Electrons are located in energy levels outside of the nucleus.
6

What did Bohr’s model of the atom include that Rutherford’s model did not have?

A
a nucleus
B
energy levels
C
electron clouds
D
smaller particles
7

Rutherford tracked the motion of tiny, positively charged particles shot through a thin sheet of gold foil. Some particles traveled in a straight line and some were deflected at different angles.Which statement best describes what Rutherford concluded from the motion of the particles?

A
Some particles traveled through empty parts of the atoms and some particles were deflected by neutrons.
B
Some particles traveled through empty parts of the atom and some particles were deflected by electrons.
C
Some particles traveled through empty parts of the atom and some particles were deflected by the orbits of atoms.
D
Some particles traveled through empty parts of the atom and some particles were deflected by small areas of high-density positive charge in atoms.
8

The atomic models after Dalton’s time included ideas about the atomic structure.Which atomic model that shows the atomic structure is missing from this set?

Question illustration
A
Niels Bohr’s model
B
Schrödinger’s model
C
Rutherford’s model
D
Thomson’s model
9

The charged particles in the beams that Thomson studied came from atoms. As these particles moved away from their original atoms, they formed a visible beam. The current model of the atom includes protons, neutrons, and electrons.What is the best use of an atomic model to explain the charge of the particles in Thomson’s beams?

A
An atom’s negative particles are surrounded by positive matter, so the positive particles are easier to remove.
B
An atom’s positive particles are surrounded by negative matter, so the negative particles are easier to remove.
C
An atom’s smaller negative particles are at a distance from the central positive particles, so the negative particles are easier to remove.
D
An atom’s larger positive particles are at a distance from the central negative particles, so the positive particles are easier to remove.
10

Which scientist developed the first model of the atom that proposed the structure of the inside of an atom?

A
Dalton
B
Bohr
C
Rutherford
D
Thomson

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