Topic 9: Chemistry of the atmosphere
AQA · GCSE · Chemistry Topic 9 10:05 English narration · English + 中文 subtitles burned in
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A gas may be invisible but still matter.
气体可能看不见，但仍会产生影响。
Build each explanation from its source, through the chemical process, to its consequence.
解释应从来源出发，经过化学过程，联系后果。
Keep a measured value separate from what you infer.
把实测值与推断分开。
Use either approximation consistently.
一致使用同一套近似值。
Do not add eighty percent nitrogen to twenty-one percent oxygen.
不能把百分之八十氮气与百分之二十一氧气相加。
Water vapour varies, and dry-air composition excludes it.
水汽含量会变化，干空气组成不包括水汽。
Pause and turn each percentage into a fraction before multiplying by the total volume.
暂停，先把百分数化为小数，再乘总体积。
State the volume unit on each answer.
每个答案都写体积单位。
Oxygen would be one hundred and five cubic centimetres.
氧气体积为105立方厘米。
The three volumes sum to five hundred, checking that the supplied fractions are consistent.
三个体积相加为500立方厘米，可检查题给比例是否一致。
Read the boxes as a causal sequence.
把方框看作因果顺序。
Volcanic gases and cooling came before the biological rise in oxygen.
火山气体与冷却先于生物导致的氧气增加。
Their widths are not a time scale or measured fractions.
方框宽度不代表时间尺度或实测比例。
Cooling changes water vapour into liquid water; it does not turn water into carbon dioxide.
冷却使水汽凝结成液态水，并不把水变成二氧化碳。
Carbon dioxide can then leave the atmosphere by dissolving and forming carbonate deposits.
二氧化碳随后可溶入水中并形成碳酸盐沉积，离开大气。
Pause and separate the observation from the exact numerical claim.
暂停，把观察与精确数值断言分开。
Ask what was actually measured, and at what time.
思考实际测了什么，以及测量发生在何时。
Other planetary atmospheres and geological evidence can strengthen a theory, but they do not make one modern observation a direct measurement of the earliest composition.
其他行星大气和地质证据可加强理论，但不能使一次现代观察变成最早大气组成的直接测量。
Photosynthesis removes carbon dioxide and releases oxygen.
光合作用吸收二氧化碳并释放氧气。
The rise took a long time and enabled animals to evolve; it was not an instant change to modern air.
氧气增加经历很长时间，使动物能够演化，并非瞬间变成现代大气。
Count the atoms rather than memorising an unbalanced shorthand.
应数原子检查，不能记住未配平的简写。
Plants both photosynthesise and respire, so discuss the balance when explaining net gas changes.
植物既进行光合作用也呼吸，因此解释净气体变化时要考虑两者的平衡。
Carbon can be stored outside the atmosphere in carbonate rock or fossil fuels.
碳可储存在大气之外的碳酸盐岩或化石燃料中。
Their starting materials and processes differ.
它们的原料与形成过程不同。
Geological storage is long-term, not literally permanent.
地质储存是长期的，并非绝对永久。
Pause and explain the missing stages.
暂停，说明缺少的阶段。
Dissolving carbon dioxide is not a process that instantly makes hydrocarbons.
二氧化碳溶解并不是瞬间生成烃的过程。
For coal, use buried plants instead.
若讨论煤，应使用埋藏植物。
Do not make photosynthesis itself the geological process, although it originally supplies carbon to biomass.
光合作用最初将碳固定到生物质，但它本身不是地质成煤过程。
The arrows show incoming sunlight, surface infrared and gas emission towards both space and the surface.
箭头表示入射阳光、地表红外线及气体向太空和地表的发射。
The box labels a process; greenhouse gases are mixed through the air rather than forming a solid lid.
方框只是过程标签，温室气体混合在空气中，并非固体盖子。
Pause and replace the mirror explanation with absorption and emission of surface infrared.
暂停，用吸收并发射地表红外线，替代镜面反射的错误解释。
The natural effect keeps Earth warmer than without these gases.
自然温室效应使地球比没有这些气体时温暖。
Increasing their amounts can change the energy balance; do not claim that all outgoing radiation is stopped.
气体增加可改变能量平衡，但不能说所有出射辐射都被阻止。
Deforestation can reduce photosynthetic removal and release stored carbon.
砍伐森林会减少光合作用移除，并可能释放储存的碳。
Methane can also arise from flooded rice cultivation.
淹水稻田也可产生甲烷。
Keep the gas linked to the stated activity.
应将气体与对应活动联系起来。
Pause and compare time scale, geographical coverage and the ability to check the methods.
暂停，比较时间尺度、地理覆盖范围以及方法能否被核查。
A must still discuss measurement uncertainty and model assumptions.
A仍须讨论测量不确定性与模型假设。
Recognising those limitations does not make B’s selected cold day a valid global conclusion.
承认这些局限，并不使B选取的冷天成为有效的全球结论。
An anomaly is a difference from a stated reference average, not an absolute Earth temperature.
异常值是相对于给定参考平均值的差，并非地球绝对温度。
Use independent mechanism evidence and multiple datasets for a causal account.
因果解释还需独立机制证据与多组数据。
Low coastal land can flood; rainfall changes can affect water supply and crops.
低洼海岸可能受淹；降雨变化会影响供水和作物。
Explain a consequence, not simply repeat that the climate changes.
应解释后果，而非仅重复气候在变化。
Pause and make the consequence specific.
暂停，具体说明后果。
Consider area, time and the ability of people or organisms to respond.
考虑范围、时间，以及人或生物应对的能力。
Thermal expansion and melting land ice can raise sea level.
海水热膨胀和陆地冰融化可使海平面上升。
Floating sea ice does not have the same direct effect as adding water from land.
浮海冰融化并不像陆地融水那样直接增加海水。
The footprint of a service includes relevant stages over its full life cycle.
服务的碳足迹包括全生命周期相关阶段。
A low-use-emission product may have greater manufacturing emissions; total the supplied stages before judging.
使用排放较低的产品可能制造排放更高，应先加总题给阶段再判断。
The stacked bars include four stages.
堆叠条包含四阶段。
B’s manufacture bar is longer, but its use-stage bar is much shorter.
B制造条更长，但使用阶段短得多。
The total comparison, not one stage, supports B under these assumptions.
在这些假设下，应以总量而非单一阶段支持B。
Pause and use the original A footprint as the percentage denominator.
暂停，百分比的分母应使用原方案A。
All numbers use the same supplied greenhouse-gas comparison unit.
所有数字采用题给的相同温室气体比较单位。
Do not divide by B when calculating reduction from A.
计算从A减少的比例，不能除以B。
A lower greenhouse footprint does not establish lower water use or less waste.
较低温室足迹并不证明用水或废物也更少。
Connect each action to its emission source and give a practical limitation.
把每项措施与排放来源联系，并给实际局限。
Captured methane may provide energy, but no single action guarantees zero footprint.
捕集甲烷可供能，但单一措施不保证零足迹。
Inspect the fuel composition before predicting products.
预测产物前先看燃料组成。
Pure hydrogen has no carbon, so burning it with oxygen cannot make carbon dioxide from those reactants alone.
纯氢无碳，因此仅由氢和氧燃烧不能生成二氧化碳。
Pause and consider every reactant source, including air rather than only the fuel.
暂停，考虑所有反应物来源，包括空气，而不仅是燃料。
Greater oxygen supply can reduce carbon monoxide and soot, yet carbon dioxide remains a product of complete carbon-fuel combustion.
增加氧气可减少一氧化碳与炭黑，但碳燃料完全燃烧仍会产生二氧化碳。
A smell test cannot rule out carbon monoxide.
凭气味不能排除一氧化碳。
Global dimming concerns incoming sunlight; greenhouse warming concerns outgoing surface infrared.
全球变暗涉及入射阳光；温室变暖涉及出射地表红外线。
Pause and separate the targeted emissions from carbon dioxide, possible carbon monoxide and high-temperature nitrogen oxides.
暂停，区分针对的排放与剩余二氧化碳、可能的一氧化碳和高温氮氧化物。
Do not claim that one filter removes every gas.
不能说一种过滤器能去除所有气体。
Atom conservation also matters: calcium oxide plus sulfur dioxide gives sulfite; sulfate requires additional oxygen.
原子守恒同样重要：氧化钙与二氧化硫生成亚硫酸盐，硫酸盐还需额外氧。
Complete the unfamiliar cases in sheets nine point one to nine point three.
完成9.1至9.3中的陌生情境。
Give a conditional recommendation, and identify the measurements or assumptions it depends on.
给出有条件的建议，并指出依赖的测量或假设。