TPO16托福阅读Passage1 Trade and the Ancient Middle East 文本+题目原文+答案解析

Trade and the Ancient Middle East

The periodic table is a chart that reflects the periodic recurrence of chemical and physical properties of the elements when the elements are arranged in order of increasing atomic number (the number of protons in the nucleus). It is a monumental scientific achievement, and its development illustrates the essential interplay between observation, prediction, and testing required for scientific progress. In the 1800's scientists were searching for new elements. By the late 1860's more than 60 chemical elements had been identified, and much was known about their descriptive chemistry. Various proposals were put forth to arrange the elements into groups based on similarities in chemical and physical properties. The next step was to recognize a connection between group properties (physical or chemical similarities) and atomic mass (the measured mass of an individual atom of an element). When the elements known at the time were ordered by increasing atomic mass, it was found that successive elements belonged to different chemical groups and that the order of the groups in this sequence was fixed and repeated itself at regular intervals. Thus when the series of elements was written so as to begin a new horizontal row with each alkali metal, elements of the same groups were automatically assembled in vertical columns in a periodic table of the elements. This table was the forerunner of the modern table.

When the German chemist Lothar Meyer and (independently) the Russian Dmitry Mendeleyev first introduced the periodic table in 1869-70, one-third of the naturally occurring chemical elements had not yet been discovered. Yet both chemists were sufficiently farsighted to leave gaps where their analyses of periodic physical and chemical properties indicated that new elements should be located. Mendeleyev was bolder than Meyer and even assumed that if a measured atomic mass put an element in the wrong place in the table, the atomic mass was wrong. In some cases this was true. Indium, for example, had previously been assigned an atomic mass between those of arsenic and selenium. Because there is no space in the periodic table between these two elements, Mendeleyev suggested that the atomic mass of indium be changed to a completely different value, where it would fill an empty space between cadmium and tin. In fact, subsequent work has shown that in a periodic table, elements should not be ordered strictly by atomic mass. For example, tellurium comes before iodine in the periodic table, even though its atomic mass is slightly greater. Such anomalies are due to the relative abundance of the "isotopes" or varieties of each element. All the isotopes of a given element have the same number of protons, but differ in their number of neutrons, and hence in their atomic mass. The isotopes of a given element have the same chemical properties but slightly different physical properties. We now know that atomic number (the number of protons in the nucleus), not atomic mass number (the number of protons and neutrons), determines chemical behavior.

Mendeleyev went further than Meyer in another respect: he predicted the properties of six elements yet to be discovered. For example, a gap just below aluminum suggested a new element would be found with properties analogous to those of aluminum. Mendeleyev designated this element "eka-aluminum" (eka is the Sanskrit word for "next") and predicted its properties. Just five years later an element with the proper atomic mass was isolated and named gallium by its discoverer. The close correspondence between the observed properties of gallium and Mendeleyev’s predictions for eka-aluminum lent strong support to the periodic law. Additional support came in 1885 when eka-silicon, which had also been described in advance by Mendeleyev, was discovered and named germanium.

The structure of the periodic table appeared to limit the number of possible elements. It was therefore quite surprising when John William Strutt, Lord Rayleigh, discovered a gaseous element in 1894 that did not fit into the previous classification scheme. A century earlier, Henry Cavendish had noted the existence of a residual gas when oxygen and nitrogen are removed from air, but its importance had not been realized. Together with William Ramsay, Rayleigh isolated the gas (separating it from other substances into its pure state) and named it argon. Ramsay then studied a gas that was present in natural gas deposits and discovered that it was helium, an element whose presence in the Sun had been noted earlier in the spectrum of sunlight but that had not previously been known on Earth. Rayleigh and Ramsay postulated the existence of a new group of elements, and in 1898 other members of the series (neon, krypton, and xenon) were isolated.

The periodic table is a chart that reflects the periodic recurrence of chemical and physical properties of the elements when the elements are arranged in order of increasing atomic number (the number of protons in the nucleus). It is a monumental scientific achievement, and its development illustrates the essential interplay between observation, prediction, and testing required for scientific progress. In the 1800's scientists were searching for new elements. By the late 1860's more than 60 chemical elements had been identified, and much was known about their descriptive chemistry. Various proposals were put forth to arrange the elements into groups based on similarities in chemical and physical properties.█The next step was to recognize a connection between group properties (physical or chemical similarities) and atomic mass (the measured mass of an individual atom of an element).█When the elements known at the time were ordered by increasing atomic mass, it was found that successive elements belonged to different chemical groups and that the order of the groups in this sequence was fixed and repeated itself at regular intervals.█Thus when the series of elements was written so as to begin a new horizontal row with each alkali metal, elements of the same groups were automatically assembled in vertical columns in a periodic table of the elements.█This table was the forerunner of the modern table.

TPO16托福阅读Passage2 Trade and the Ancient Middle East 题目

Question 1 of 14:  The phrase “interplay” in the passage is closest in meaning to

A. Sequence

B. Interpretation

C. Requirement

D. Interaction

Question 2 of 14: According to paragraph 1, what pattern did scientists notice when the known elements were written in order of increasing atomic mass?

A. The elements of the group of alkali metals were the first elements in the order of increasing atomic mass.

B. Repetition of the same atomic masses for elements in different groups appeared.

C. Elements with similar chemical properties appeared in the listing at regular intervals.

D. Elements were chemically most similar to those just before and after them in the order.

Question 3 of 14: In paragraph 2, what is the author's purpose in presenting the information about the decision by Meyer and Mendeleyev to leave gaps in the periodic table?

A. To illustrate their confidence that the organizing principles of the periodic table would govern the occurrence of all chemical elements B. To indicate that some of their analyses of periodic physical and chemical properties were later found to be wrong

C. To support the idea that they were unwilling to place new elements in the periodic table

D. To indicate how they handled their disagreement about where to place new elements

Question 4 of 14:  What reason does the author provide for the claim that “Mendeleyev was bolder than Meyer"?

A. Mendeleyev corrected incorrect information Meyer had proposed.

B. Mendeleyev assumed that some information believed to be true about the elements was incorrect.

C. Mendeleyev argued that Meyer had not left enough gaps in the periodic table.

D. Mendeleyev realized that elements were not ordered by atomic mass in the periodic table.

Question 5 of 14: According to paragraph 2, why did Mendeleyev suggest changing the atomic mass of indium?

A. Because indium did not fit into the periodic table in the place predicted by its atomic mass

B. Because there was experimental evidence that the atomic mass that had been assigned to indium was incorrect

C. Because there was an empty space between cadmium and tin in the periodic table

D. Because the chemical properties of indium were similar to those of arsenic and selenium

Question 6 of 14: It can be inferred from paragraph 2 that tellurium comes before iodine in the periodic table even though tellurium's atomic mass is slightly greater because

A. iodine is less common than tellurium

B. both iodine and tellurium have no isotopes

C. the chemical behavior of tellurium is highly variable

D. the atomic number of tellurium is smaller than that of iodine

Question 7 of 14:  The phrase "abundance” in the passage is A.closest in meaning to

A.weight

B. requirement

C. plenty

D. sequence

Question 8 of 14: The phrase “analogous to” in the passage is closest in meaning to

A. predicted by

B. expected of

C. similar

D. superior

Question 9 of 14: Paragraph 3 suggests that Mendeleyev predicted the properties of eka-aluminum on the basis of

A. the atomic mass of aluminum

B. the position of the gap in the periodic table that eka-aluminum was predicted to fill  

C. the similarity of eka-aluminum to the other five missing elements

D. observation of the properties of gallium

Question 10 of 14: It can be inferred from paragraph 3 that the significance of the discovery of gallium was that it supported which of the following?

A. The idea that aluminum was correctly placed in the periodic table

B. Mendeleyev's prediction that eka-silicon would be discovered next

C. The organizing principle of the periodic table

D. The idea that unknown elements existed

Question 11 of 14:  Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.

A. Ramsay found evidence of helium in the spectrum of sunlight before he discovered that the element was also contained in natural gas deposits on Earth.

B. Ramsay thought he had discovered a new element present in natural gas deposits, but he was wrong since that element had been previously observed elsewhere on Earth

C. After Ramsay had discovered a new element, called helium, in natural gas deposits on Earth, he also found evidence of its presence in the Sun.

D. Ramsay later discovered that helium, an element that was already known to be present in the Sun, was also present in natural gas deposits on Earth.

Question 12 of 14: The word “postulated” in the passage is closest in meaning to

A. hypothesized

B. discovered

C. reported

D.generated

Question 13 of 14: Look at the four squares █ that indicate where the following sentence could be added to the passage. Where would the sentence best fit?

It was a natural idea to break up the series of elements at the points where the sequence of chemical groups to which the elements belonged began to repeat itself.

A. The next step was to recognize a connection between group properties (physical or chemical similarities) and atomic mass (the measured mass of an individual atom of an element).

B. When the elements known at the time were ordered by increasing atomic mass, it was found that successive elements belonged to different chemical groups and that the order of the groups in this sequence was fixed and repeated itself at regular intervals.

C. Thus when the series of elements was written so as to begin a new horizontal row with each alkali metal, elements of the same groups were automatically assembled in vertical columns in a periodic table of the elements.

D. This table was the forerunner of the modern table.

Question 14 of 14: To review passage, click View Text.

The periodic table introduced by Meyer and Mendeleyev was the forerunner of the modern table of elements.

A. Lord Rayleigh provided evidence that the structure of the periodic table limited the potential number of elements.

B. Mendeleyev and Meyer organized the known elements into a chart that revealed periodic recurrences of chemical and physical properties.

C. Mendeleyev's successful prediction of the properties of then-unknown elements lent support to the acceptance of the periodic law.

D. Ramsay and Lord Rayleigh challenged the importance of the chemical research that Henry Cavendish had done a century earlier.

E. Isotopes of a given element have exactly the same physical properties, but their chemical properties are slightly different

F. In the 1890's, Ramsay and Lord Rayleigh isolated argon and proposed the existence of a new series of elements.

TPO16托福阅读Passage2Trade and the Ancient Middle East真题解析

Question 1 of 14

正确答案：D

解析：interplay“相互作用”，所以D的interaction正确。从单词本身看，inter表示“在……之间”，play是“起……作用”，所以interplay是“相互作用”。原句说观察、预测与实验相互作用，所以答案是interaction，A“顺序”B“解释”C“要求”都错误。

Question 2 of 14

正确答案：C

解析：以increasing atomic mass做关键词定位至第一句倒数第三句，提到一些连续的元素却分属不同的化学组，并且发现在这种排列方式下，元素群组的顺序是固定的且定期重复。所以正确答案是C。A的alkali metals，B same atomic mass原文都没提及；D 相邻元素性质相近，与原文相反。

Question 3 of 14

正确答案：A

解析：修辞目的题，根据题干关键词leave gaps定位到第二段第二句，提到两个人都非常有远见，在周期表中给没发现的元素留了空隙，也就是A说的他们足够自信认为元素周期律适用于所有元素；B的wrong和C的unwilling都跟原文相反；D的disagreement原文未提及。

Question 4 of 14

正确答案：B

解析：修辞目的题，先找到两个人名，门捷列夫比迈耶更为大胆，他甚至做出假设，如果周期表按原子质量排列，但元素位置不对的话，那么原子质量也是错的。也就是选项B说的门捷列夫认为以前被大家所认识到的一些东西是错误的。两个人的意见是一样的，只是门捷列夫更进一步，所以A和C说两者的意见有差异不正确；D说不是按原子量排序，错误

Question 5 of 14

正确答案：A

解析：以changing the atomic mass of indium做关键词定位至第五句、第六句，提到先前按原子质量计算，铟应该在砷和硒之间，但由于元素周期表中砷和硒之间没有空位，所以铟的原子量是错的。因为前面提到如果原子量把元素放错了位置，就说明原子量是错的，后一句是为了证明这个观点的，所以答案是A。B的experimental evidence和D的化学性质相似原文都未提及；C有space与原文相反。

Question 6 of 14

正确答案：D

解析：以tellurium comes before iodine做关键词定位至第二段倒数第五句for example处，但这句话只是一个例子，所以往前看，提到元素不应该严格按照原子量排列，而且最后一句又提到决定元素化学性质的是原子数目，不是原子质量，也就是应该按照原子数目排列，所以答案D正确。A“谁更不普遍”，B“有没有同位素”还有C“化学性质多变”没有信息能推出。

Question 7 of 14

正确答案：C

解析：abundance“丰富”，答案是plenty。原句提到这种异常，也就是尽管碲的原子质量大却排在前面这种异常是由于同位素的什么，然后后面就解释每种同位素的质子数量相同，但中子数不同，导致原子质量不同。碲的原子质量大，可以推出同位素比较丰富，所以答案是plenty，B“要求”D“顺序”明显不正确；A“重量不同”原文已经直接说了不用再说一遍。

Question 8 of 14

正确答案：C

解析：analogous to“可类比的，相似的”，所以答案similar to正确。原句提到铝元素之下的空白元素是与铝的性质_______的，前文都说了相邻的元素属于不同的群组，而且群组会相隔固定数目的元素出现，根据常识也知道元素周期表中上下两元素性质相似，所以答案是similar。

Question 9 of 14

正确答案：B

解析：以eka-aluminum做关键词定位至第三段第三句，但这句话只提到预测了eka的性质，没提根据什么预测的，再看上一句，提到eka是铝之下的那个空格里的元素，而且跟铝性质相似，所以答案是B，根据元素周期表的空缺预测了这个元素的性质。

Question 10 of 14

正确答案：C

解析：以gallium做关键词定位至第三段倒数第三句，但这句话只是提到这样质量的元素被隔离出来被命名为锗，没提支持什么，往下看提到锗的发现支持了元素周期律，所以答案是C。

Question 11 of 14

正确答案：D

解析：原句的主干信息是：Ramsay研究一种气体并发现它是氦，补充信息是：他在研究大气储备的一种气体时发现它是氦，另外该元素在太阳中存在，并且很早就被发现存在于太阳光谱中，但是之前并没有在地球上找到过。A错在原文没有体现这样的时间先后顺序；B不符合原文意思，原文没有提到Ramsay认为自己发现了新元素，另外之前地球别的地方也没观察到该元素；C，氦在太阳光谱中并非是Ramsay发现的，错误。

Question 12 of 14

正确答案：A

解析：postulate“推断，推测”，所以hypothesize正确。原句提到这两个人____一组新元素的存在，接着后面的人分离出了这些元素。既然是后面的人分离的，discover和report就不正确，因为这两个词有他们两个发现的意思；generate完全不正确，这两个人不能产生元素。

Question 13 of 14

正确答案：C

解析：三个过渡点，分别是名词chemical groups，名词sequence和动词词组repeat itself，这句话说的是元素所在的化学群组的次序开始重复，很自然也就因此将一系列的元素断开。只有C选项前面提到连续的元素属于不同的化学群组，它们的次序是固定的，而且有规律地重复。因此在意义上是有联系的，都出现了与“重复”相关的信息，选C。

Question 14 of 14

正确答案：BCF

解析： B选项对应选项对应原文第一段后半部分，正确；C选项选项对应原文第三段最后两句，正确；F选项对应最后一段最后一句话，正确。

A选项错误，原文没提到他的研究提供了元素周期表限制元素数量的证据，不选；D选项错误，原文没提到他们俩挑战了卡文迪许，不选；E选项错误，与原文第二段的描述相反，原文说的是化学性质一样，但物理性质有些许差别。

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