Which is a way that the model of the atom became stronger through new experiments? (1 point) New technology allowed scientists t
o show that the atom is indivisible. It took new data to show that positive charge is not spread throughout an atom. By deflecting alpha particles, Rutherford first observed the neutron. The neutron could not be detected until Cathode-Ray Tubes were invented. Score: 0 of 1 27. [04.04] Some say that the fact that scientific models change over time is proof that scientists from earlier historical eras were bad at their jobs. Which statement best argues against this position? (1 point) Scientists can only use the information available at the time to create their models. Scientific models do not always get more accurate over time. Mathematical models are always more accurate than non-mathematical models. The ultimate goal of science is to produce accurate models that predict behavior. Score: 0 of 1 28. [04.04] Many scientists contributed to the current model of atoms. Which of the following offers a hypothesis on how people's backgrounds and interests influence their work? (1 point) A person with more activities and interest is more creative and intelligent. A person's background and interests can give him a unique perspective in his research. If a person has an outside influence on his work, it is more credible to the general public. A person's involvement in arts and literature will help them notice more details in their research. Score: 0 of 1 29. [04.04] Which best describes a way that an experiment contradicted an existing model of the atom? (1 point) Thomson showed that neutrons must be located in the center of an atom. Rutherford showed that the atom must have a nucleus. Bohr showed that atoms must contain negative charges. Chadwick showed that atoms cannot contain neutral particles. Score: 1 of 1 30. [04.04] Which is true about scientific theories? (1 point) They are the result of a single experiment. They are the results of many experiments over a long period of time. They are proposed by scientists who wish to investigate a new topic. They are only based on the most recent evidence. Score: 1 of 1 31. [04.04] Why does the modern atomic theory used today represent the best explanation scientists have to offer? (1 point) Modern technology supports the current atomic theory. The model of the atom has not changed much in over 75 years. The modern atomic theory contains over 200 years of research. Scientists have not been successful in disproving the atomic theory. Score: 1 of 1 32. [04.04] Which best describes the current atomic model? (1 point) It is not an exact representation of the atom, but is close enough to be very useful. It is not an exact representation of the atom, so it is not very useful. It describes exactly how the atom behaves in every circumstance. It is so trusted that no new information could possibly cause a change to the model. Score: 1 of 1 Objectives: ID Mastery Description CCSS.ELA-Literacy.W.9-10.2a Introduce a topic; organize complex ideas, concepts, and information to make important connections and distinctions; include formatting (e.g., headings), graphics (e.g., figures, tables), and multimedia when useful to aiding comprehension. Close
1) In the early 20th centuries, there were a lot of theories regarding the smallest units of matter. Thomson had already discovered the electron in 1897 and Planck had brought forth a rudimentary quantum theory. A major step ahead were Ernest Rutherford's experiments; he shot alpha particles (positively charged helium nuclei) at some atoms and he observed that some a particles were deflecting a lot, while others were deflecting just a bit. This meant, that the positive charge in the atoms was not spread around the atom (as the Raisin Bread Model assumed; electrons were raising in the bread that was a region of positive charge) but that the positive charge was condensed. Cathode ray tubes were used for the detection of electrons and the atom clearly has some smaller components, even if at first we thought that it was indivisible. Hence the correct answer to the first question is that: <span> It took new data to show that positive charge is not spread throughout an atom. 2)The next question needs critical thinking. While it is true, that models do not always improve throughout the ages (for example Einstein famously added a mistaken correction to his work on relativity theory), this does not counter the proposition. It is also true that mathematical models are more useful (when they can be solved for) than non-mathematical models, this has no correlation to the proposition. The ultimate goal of science is to find a model that predicts behaviour, but that is what the older scientists were trying to do too; they might have gotten the causes wrong, but they still could regularly predict the results of experiments and we have not gotten much better in that aspect. The fact that argues the best against the excerpt's position is the fact that scientists can only work with the data that they have at that point in time. It is easy to judge Galileo for not understanding Kepler's laws but the mathematics for that discovery were still out of his reach; similarly, in microbiology it took a long time for people to understand cells, even though there were lots of observations; the microscopes though were not strong enough. The advances that these pioneers made constituted a huge step in their own right given the common knowledge at their time and given this restriction they were not worse at their jobs than present-time scientists. 3) We have that people that people that are influenced by others in their research, do not necessarily have more public acceptance and neither do their findings. While it might be true that a person with more activities is more creative and intelligent, there have been some exemplary cases of scientins like Hardy, von Neumann, Dirac etc. that did not have many other activities other than research; it is obvious that these were still highly creative and intelligent individuals. A person's involvement with art is again not a good sign of research quality or attentiveness to detail. The correct answer is that the differing backgrounds and interest CAN (attention to phrasing; the other alternatives had will in place of can) lead to a unique perspective to scientifi work. This is often the case with research on the boundary of 2 scientific fields. 4) Thomson discovered the existence of the electrons; the last statement is physically wrong since Atoms contain nucleons that are neutral. Since atoms were neutral and had positive charges, it was apparent that atoms needed to have negative charges inside them before Bohr. The correct answer is that Rutherford showed that the atom must have a nucleus where all of its positive charge is accumulated. 5) Scientific theories need the affirmation of many experiments and thus are established after long experimentation and theoretical work. Scientific theories can be established by responding to a new topic, but it is quite usual that completely new theories are proposed for phenomena that were considered known; Galileo's theory is a prime example and in more recent years the contributions to Black Hole theory from Stephen Hawking could qualify as such. Finally, scientific theories try to integrate all the data we have accummulated, from all periods. While some old data may have inaccuracies or not be that easily accessible, it does not mean that we can dismiss them when creating a new scientific theory. </span>
