고등 논술 자료함
경희대 2005학년도 수시1학기 논술고사 (자연)
[논 제]
1. 제시문 [가]에서 설명하고 있는 X와 Y가 각각 무엇인지 순서대로 원고지의 첫번째 줄에 쓰시오.
2. 제시문 [나]와 [다]에서 언급된 내용에 근거하여 각각의 경우에 Y가 생성되는 경로가 어떻게 다른지 반응식을 이용하여 간단히 설명하시오. 원고지의 두번째 줄부터 네번째 줄 구간에 쓰시오.
3. Y가 광분해 되기 위해서는 파장이 얼마 이하인 빛이 필요한지 원고지의 다섯번째 줄에 쓰시오. (단, 플랑크 상수 J.s, 빛의 속도 m/s 그리고 아보가드로 상수는 mol-1 이다.)
4. 제시문 [나]와 [다]는 Y가 지구상의 어디에 존재하는가에 따라 우리에게 이로운 물질이 될 수도 있고 해로운 물질이 될 수도 있음을 보여 준다. 각각의 역할을 순서대로 자세히 설명하고 제시문 [가]에서 언급한 Y의 성질 중 어떠한 성질이 각각의 역할에서 중요하게 작용했는지 600자 내외로 논술하시오.
5. Y와 같이 존재 위치나 사용처에 따라 그 역할이 확연히 달라질 수 있는 것의 예를 들고, 이러한 것들을 사용할 때 고려하여야 할 점에 대하여 자유롭게 400자 내외로 논술하시오.
[가] Molecule X consists of the element which is most abundant on this planet. The earth's crust is 46.6% this element by weight. The electron configuration1) of the atom of this element suggests that neutral atoms of this element can achieve an octet2) of valence electrons3) by sharing two pairs of electrons to form a double bond4). At temperatures below -183 °C, molecule X condenses to form a liquid with a characteristic light blue color.
Molecule Y is an allotrope of molecule X. By definition, allotropes are different forms of an element. Because they have different structures, allotropes have different chemical and physical properties. In standard state, molecule Y is a pale blue gas. It boils at the temperature of -111.9 °C. In liquid state it has a deep blue color.
Molecule Y is an unstable molecule with a sharp, pungent odor that slowly decomposes to molecule X. Exposure to molecule Y at higher concentrations leads to coughing, rapid beating of the heart, chest pain and general body pain. One of the characteristic properties of molecule Y is its ability to absorb radiation in the ultraviolet portion of the spectrum, thereby providing a filter that protects us from exposure to high-energy ultraviolet radiation emitted by the sun. Molecule Y is much more active chemically than molecule X. It can be used to purify water, to sterilize air, and to bleach certain foods.
[나] The atmosphere can be divided into several distinct layers, as shown in Figure 1. The sun emits lights over a broad range of wavelengths, with the highest intensity at about 500 nm, in the visible region of the spectrum. The intensity at wavelengths down to 100 nm in the ultraviolet is quite substantial, and because the energy carried by a photon is inversely proportional to the wavelength, the ultraviolet photons carry much more energy than do photons5) of visible light. If they were able to penetrate to the earth's surface in substantial numbers, these photons could do a great deal of damage to living organisms. The outer portions of the atmosphere play a crucial role in preventing this through the photodissociation6) of molecule X.
Rather few photons with wavelengths less than 200 nm are able to penetrate to the stratosphere7), but those that do establish a small concentration of photodissociated atoms of molecule X in that layer. These atoms can collide with the much more prevalent molecules of X to form highly excited molecules of Y. The excited state of molecule Y can dissociate in a unimolecular8) reaction back to molecule X and its atom. Alternatively, if another atom or molecule collides with it soon enough, some of its excess energy can be transformed to that atom or molecule.
The net effect of this reaction is to produce a small concentration of molecule Y in the stratosphere. In the stratosphere, molecule Y photodissociates readily to molecule X and its atom in a reaction that requires about 106 kJ per mole of molecule Y, much less than the dissociation of molecule X.
This process occurs with greatest efficiency for wavelengths between 200 and 350 nm. The energy of light of these wavelengths is too small to be absorbed by molecule X, but quite large enough to damage organisms at the earth's surface. The balance between formation and photodissociation leads to a steady-state concentration of more than 1015 molecules of Y per liter in the stratosphere.
[다] The troposphere9) is most directly and immediately influenced by human activities - by the gases or small particles put into the air by automobiles, power plants, and factories. Some pollutants have long lifetimes and are spread fairly evenly over the earth's surface; others attain large concentrations only around particular cities or industrial areas. The oxides of nitrogen are major air pollutants. Their persistence in the atmosphere shows the importance of kinetics, as opposed to thermodynamics, in the chemistry of atmosphere. All of the oxides of nitrogen are thermodynamically unstable with respect to the elements at 25 °C, as shown by their positive free energies of formation. They form whenever air is heated to high enough temperatures, either in an industrial process or in the engine of a car. They accumulate to much higher than equilibrium10) concentrations because their rates of decomposition are slow. The interconversion between NO, NO2, and N2O4 is rapid and strongly temperature- dependent, so in pollution reports they are generally grouped together as NOx. Photochemical smog is formed by the action of light on nitrogen dioxide, followed by subsequent reaction to produce molecule Y.
Although molecule Y is beneficial in preventing radiation from penetrating to the earth's surface, it is quite harmful in direct contact with organisms. Levels of 10 to 15 ppm are sufficient to kill small mammals, and a concentration as low as 3 ppm is enough to trigger an alert. In addition, molecule Y reacts with incompletely oxidized organic compounds from gasoline and with nitrogen oxides in the air to produce harmful irritants such as methyl nitrate.
[주]
1) electron configuration: a representation of the occupancy of orbitals by the electrons in an atom
2) octet: a group or set of eight
3) valence electrons: electrons in the outermost unfilled shell of an atom, which can take part in chemical bonding
4) double bond: a chemical bond consisting of two covalent bonds between two atoms in a molecule
5) photon: a smallest possible unit of electromagnetic radiation (e.g. light)
6) photodissociation: reversible decomposition of a molecule by action of radiant energy, especially light
7) stratosphere: the upper part of the atmosphere which extends outward about 11 to 16 kilometers from the earth's surface
8) unimolecular: involving a single molecule
9) troposphere: the part of the atmosphere which is below the stratosphere
10) equilibrium: a state of balance between opposing actions affecting a system that results in a state of dynamic balance (e.g. when a chemical reaction and its reverse reaction take place at equal rates)
※ 유의사항
① 띄어쓰기를 포함하여 1,101자~1,200자 이내로 논술하시오.
② 제목은 쓰지 말고 특별한 표시를 하지 마시오.
③ 예시문 속의 문장을 그대로 쓰지 마시오.
④ 반드시 본교에서 지급된 필기구를 사용하시오.
⑤ 본교에서 지급한 필기구를 사용하지 않거나, 답안지에 특별한 표시를 한 경우(예: 감사합니다. 등), 원고지의 일정분량 이상을 작성하지 않은 경우에는 감점 또는 0점 처리합니다.
[논 제]
1. 제시문 [가]에서 설명하고 있는 X와 Y가 각각 무엇인지 순서대로 원고지의 첫번째 줄에 쓰시오.
2. 제시문 [나]와 [다]에서 언급된 내용에 근거하여 각각의 경우에 Y가 생성되는 경로가 어떻게 다른지 반응식을 이용하여 간단히 설명하시오. 원고지의 두번째 줄부터 네번째 줄 구간에 쓰시오.
3. Y가 광분해 되기 위해서는 파장이 얼마 이하인 빛이 필요한지 원고지의 다섯번째 줄에 쓰시오. (단, 플랑크 상수 J.s, 빛의 속도 m/s 그리고 아보가드로 상수는 mol-1 이다.)
4. 제시문 [나]와 [다]는 Y가 지구상의 어디에 존재하는가에 따라 우리에게 이로운 물질이 될 수도 있고 해로운 물질이 될 수도 있음을 보여 준다. 각각의 역할을 순서대로 자세히 설명하고 제시문 [가]에서 언급한 Y의 성질 중 어떠한 성질이 각각의 역할에서 중요하게 작용했는지 600자 내외로 논술하시오.
5. Y와 같이 존재 위치나 사용처에 따라 그 역할이 확연히 달라질 수 있는 것의 예를 들고, 이러한 것들을 사용할 때 고려하여야 할 점에 대하여 자유롭게 400자 내외로 논술하시오.
[가] Molecule X consists of the element which is most abundant on this planet. The earth's crust is 46.6% this element by weight. The electron configuration1) of the atom of this element suggests that neutral atoms of this element can achieve an octet2) of valence electrons3) by sharing two pairs of electrons to form a double bond4). At temperatures below -183 °C, molecule X condenses to form a liquid with a characteristic light blue color.
Molecule Y is an allotrope of molecule X. By definition, allotropes are different forms of an element. Because they have different structures, allotropes have different chemical and physical properties. In standard state, molecule Y is a pale blue gas. It boils at the temperature of -111.9 °C. In liquid state it has a deep blue color.
Molecule Y is an unstable molecule with a sharp, pungent odor that slowly decomposes to molecule X. Exposure to molecule Y at higher concentrations leads to coughing, rapid beating of the heart, chest pain and general body pain. One of the characteristic properties of molecule Y is its ability to absorb radiation in the ultraviolet portion of the spectrum, thereby providing a filter that protects us from exposure to high-energy ultraviolet radiation emitted by the sun. Molecule Y is much more active chemically than molecule X. It can be used to purify water, to sterilize air, and to bleach certain foods.
[나] The atmosphere can be divided into several distinct layers, as shown in Figure 1. The sun emits lights over a broad range of wavelengths, with the highest intensity at about 500 nm, in the visible region of the spectrum. The intensity at wavelengths down to 100 nm in the ultraviolet is quite substantial, and because the energy carried by a photon is inversely proportional to the wavelength, the ultraviolet photons carry much more energy than do photons5) of visible light. If they were able to penetrate to the earth's surface in substantial numbers, these photons could do a great deal of damage to living organisms. The outer portions of the atmosphere play a crucial role in preventing this through the photodissociation6) of molecule X.
Rather few photons with wavelengths less than 200 nm are able to penetrate to the stratosphere7), but those that do establish a small concentration of photodissociated atoms of molecule X in that layer. These atoms can collide with the much more prevalent molecules of X to form highly excited molecules of Y. The excited state of molecule Y can dissociate in a unimolecular8) reaction back to molecule X and its atom. Alternatively, if another atom or molecule collides with it soon enough, some of its excess energy can be transformed to that atom or molecule.
The net effect of this reaction is to produce a small concentration of molecule Y in the stratosphere. In the stratosphere, molecule Y photodissociates readily to molecule X and its atom in a reaction that requires about 106 kJ per mole of molecule Y, much less than the dissociation of molecule X.
This process occurs with greatest efficiency for wavelengths between 200 and 350 nm. The energy of light of these wavelengths is too small to be absorbed by molecule X, but quite large enough to damage organisms at the earth's surface. The balance between formation and photodissociation leads to a steady-state concentration of more than 1015 molecules of Y per liter in the stratosphere.
[다] The troposphere9) is most directly and immediately influenced by human activities - by the gases or small particles put into the air by automobiles, power plants, and factories. Some pollutants have long lifetimes and are spread fairly evenly over the earth's surface; others attain large concentrations only around particular cities or industrial areas. The oxides of nitrogen are major air pollutants. Their persistence in the atmosphere shows the importance of kinetics, as opposed to thermodynamics, in the chemistry of atmosphere. All of the oxides of nitrogen are thermodynamically unstable with respect to the elements at 25 °C, as shown by their positive free energies of formation. They form whenever air is heated to high enough temperatures, either in an industrial process or in the engine of a car. They accumulate to much higher than equilibrium10) concentrations because their rates of decomposition are slow. The interconversion between NO, NO2, and N2O4 is rapid and strongly temperature- dependent, so in pollution reports they are generally grouped together as NOx. Photochemical smog is formed by the action of light on nitrogen dioxide, followed by subsequent reaction to produce molecule Y.
Although molecule Y is beneficial in preventing radiation from penetrating to the earth's surface, it is quite harmful in direct contact with organisms. Levels of 10 to 15 ppm are sufficient to kill small mammals, and a concentration as low as 3 ppm is enough to trigger an alert. In addition, molecule Y reacts with incompletely oxidized organic compounds from gasoline and with nitrogen oxides in the air to produce harmful irritants such as methyl nitrate.
[주]
1) electron configuration: a representation of the occupancy of orbitals by the electrons in an atom
2) octet: a group or set of eight
3) valence electrons: electrons in the outermost unfilled shell of an atom, which can take part in chemical bonding
4) double bond: a chemical bond consisting of two covalent bonds between two atoms in a molecule
5) photon: a smallest possible unit of electromagnetic radiation (e.g. light)
6) photodissociation: reversible decomposition of a molecule by action of radiant energy, especially light
7) stratosphere: the upper part of the atmosphere which extends outward about 11 to 16 kilometers from the earth's surface
8) unimolecular: involving a single molecule
9) troposphere: the part of the atmosphere which is below the stratosphere
10) equilibrium: a state of balance between opposing actions affecting a system that results in a state of dynamic balance (e.g. when a chemical reaction and its reverse reaction take place at equal rates)
※ 유의사항
① 띄어쓰기를 포함하여 1,101자~1,200자 이내로 논술하시오.
② 제목은 쓰지 말고 특별한 표시를 하지 마시오.
③ 예시문 속의 문장을 그대로 쓰지 마시오.
④ 반드시 본교에서 지급된 필기구를 사용하시오.
⑤ 본교에서 지급한 필기구를 사용하지 않거나, 답안지에 특별한 표시를 한 경우(예: 감사합니다. 등), 원고지의 일정분량 이상을 작성하지 않은 경우에는 감점 또는 0점 처리합니다.