Section 2, Lesson 1: Test Review

Which of these discoveries contradict components of Dalton's atomic theory?

- Atoms contain smaller particles: protons, neutrons, and electrons. - Atoms of a given element can have different numbers of neutrons. - Nuclear reactions can change an atom of one element into an atom of another element.

Describe two ways the material in this lesson illustrates the importance of creativity in scientific investigations.

- Dalton used creativity to modify Proust's experiment and interpret the results. - Thomson used creativity to interpret the results of the cathode ray tube experiment.

Why is Dalton credited with proposing the first atomic theory if Democritus was talking about atoms almost 2,200 years earlier?

- Democritus' ideas were not supported by evidence - Dalton's theory was the first scientific theory because it relied on scientific investigative processes. - Dalton's theory was supported by evidence and repeated investigation.

Which is a component of John Dalton's atomic theory?

A reaction can create or destroy atoms as well as rearrange them

Which best describes the effect of J.J. Thomson's discovery?

Cathode ray tubes were no longer used in experiments due to poor results.

Who was the first to propose the existence of atoms?

Democritus

Which statement is most likely true?

Ernest Rutherford's experiment led the nuclear model of the atom.

Which statement best describes John Dalton's use of creativity in his work?

He reinterpreted and restarted Joseph Proust's results.

Which activity is the best demonstration of J.J. Thompson's use of creativity in his work?

Interpreting the results of his experiment

How did the development of the earliest idea about atoms differ from the later work of scientists?

It was based on the thoughts of an early philosopher.

Which scientist is credited with developing the first scientific atomic theory

John Dalton

Which scientist provided a foundation for John Dalton's work on the atomic structure?

Joseph Proust

If the plum pudding model of the atom was correct, was should the results of Rutherford's experiment?

Most of the positively charged particles should bounce back at a range of angles as they collide with the atoms in the foil; only a few should pass straight through the foil.

Who was the first to propose the existence of atoms?

NOT John Dalton

What did Ernest Rutherford's gold foil experiment demonstrate about an atom?

Positive charge occupies a very small volume in the atom.

Explain how the atomic theory was modified from Dalton's theory to Rutherford's. Include an explanation of why the theory was modified.

Rutherford's results showed that most of an atom is empty space and that the mass is concentrated in the center of the atom. This discovery required the plum pudding model to revised.

Which statement best explains why the atomic theory developed efficiently?

Scientists had used creativity in their investigations.

What did J.J. Thomson observe when he applied electric voltage to cathode ray tube in his famous experiment?

The glass opposite of the negative electrode started to glow.

Whose work directly resulted in the development of an atomic model that has negative electrons stuck within a sea of positive material?

Thomson