Entry Exam Category: High School Equivalency Exams
Course: General Education Development (GED)
Exam: GED Science and Practice Test
Practice Question
Extract
In the nineteenth century, scientists determined that atoms consist of electrons and protons. J. J. Thomson modeled the atom as a uniform arrangement of electrons inside a positive sphere of charge. In the early twentieth century, Earnest Rutherford concluded from experiments that most of the mass and all of the positive charge of atoms were concentrated in the center of the atom, with the negatively charged electrons orbiting the center.
Which statement describes one feature of the Rutherford-Bohr atom model that the Thomson model does not share?
Answer Choices
- A: The Rutherford-Bohr model identifies different elements by the numbers of particles present.
- B: The Rutherford-Bohr model maintains the observed neutral charge of atoms.
- C: The Rutherford-Bohr model correctly describes the types of particles in the atom.
- D: The Rutherford-Bohr model restricts the positive charge of the atom to the nucleus.
Correct Answer: D
Rationale: The Rutherford-Bohr model places the positive charge in the nucleus, unlike Thomson’s 'plum pudding' model, which distributes positive charge uniformly.