为什么镁条能在水上烧起来？
Why can a magnesium strip burn on water?
镁相当活泼，高温下能夺取水中的氧生成氧化镁并放出氢气，反应放热使燃烧持续，所以金属并非都怕火。
Magnesium is reactive enough to take oxygen from water at high temperature, forming MgO and H2; the exothermic reaction sustains burning—metals aren't all fireproof.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#镁 #燃烧 #活泼金属
拉瓦锡为什么被称为近代化学之父？他最重要的实验是什么？
Why is Lavoisier called the father of modern chemistry, and what was his most important experiment?
拉瓦锡最重要的贡献是用精确的天平做定量实验，推翻了燃素说。他在密闭容器中加热汞，发现汞与一部分空气化合成红色粉末（氧化汞），容器中空气减少约五分之一；再把粉末加热，得到汞并放出一种气体，这种气体恰好支持燃烧和呼吸，这就是氧气。他由此确立了燃烧是物质与氧的反应，以及质量守恒定律：化学反应前后物质的总质量不变。他还规范了化学命名法，把化学从定性的猜测变成定量的科学。
Lavoisier's greatest contribution was replacing the phlogiston theory with precise, quantitative weighing. In a sealed vessel he heated mercury and found it combined with about a fifth of the air into a red powder (mercury oxide); heating that powder released a gas which supported burning and breathing - oxygen. He concluded that combustion is a reaction with oxygen and established the law of conservation of mass: the total mass of substances is unchanged by a chemical reaction. His systematic naming rules also turned chemistry from qualitative guesswork into a quantitative science.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
傅献彩 等,《物理化学》第5版,高等教育出版社,2005
Fu Xiancai et al., Physical Chemistry, 5th ed., Higher Education Press, 2005
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9787040167696（按标识回读: 物理化学(第五版)上册）
#拉瓦锡 #质量守恒 #燃烧
为什么烟花会放出臭味气体？
Why can fireworks smell bad?
火药含硫，燃烧产生二氧化硫等有刺激性气味的气体。
Powder contains sulfur whose combustion makes pungent sulfur dioxide.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#烟花 #二氧化硫 #硫
拉瓦锡怎样推翻了燃素说？
How did Lavoisier overthrow the phlogiston theory?
他称量金属煅烧后增重、且空气体积减少，证明燃烧是物质与氧结合，而不是放出虚构的燃素。
He showed metals gain mass and air volume drops on burning, proving combustion is combination with oxygen, not release of imaginary phlogiston.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#拉瓦锡 #燃素说 #氧气
诺贝尔为什么要发明炸药，后来为何设立诺贝尔奖？
Why did Nobel invent dynamite, and why the Nobel Prize?
他把易炸的硝化甘油吸附进硅藻土做成稳定的炸药用于工程；晚年立遗嘱把财富设奖，奖励对人类有贡献的科学家。
He stabilized volatile nitroglycerin in diatomite for safe engineering use; in his will he left his fortune to prize scientists who benefit humanity.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#诺贝尔 #炸药 #历史
为什么充分预混的烃火焰呈蓝色，而扩散燃烧或富燃料火焰发黄光？这两种颜色对应的发光过程有何本质不同？
Why does a well-premixed hydrocarbon flame look blue while a diffusion or fuel-rich flame glows yellow, and what fundamentally different processes produce these two colours?
蓝光来自化学发光：预混火焰反应区内，激发态自由基CH*、C₂*跃回基态时发出位于蓝绿区的特征谱带。黄光来自炽热烟黑：富燃料缺氧区中，烃经乙炔与多环芳烃途径聚成纳米级烟黑颗粒，被加热到约2000 K后发射近似黑体的连续谱。前者是分子尺度的电子跃迁，后者是凝相颗粒的热辐射，故黄色火焰通常意味着不完全燃烧并伴随烟黑生成。
Blue light is chemiluminescence: in the reaction zone of a premixed flame, electronically excited radicals such as CH* and C2* emit characteristic band radiation in the blue-green region as they fall back to the ground state. Yellow light comes from glowing soot: in oxygen-starved, fuel-rich pockets, hydrocarbons grow through acetylene and polycyclic-aromatic pathways into nanometre soot particles that radiate a near-blackbody continuum at about 2000 K. Molecular-scale electronic transitions versus thermal radiation from condensed particles is why a yellow flame usually signals soot formation and incomplete combustion.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
J. Warnatz, U. Maas, R. W. Dibble, Combustion: Physical and Chemical Fundamentals, Modeling and Simulation, Experiments, Pollutant Formation, 第4版, Springer, 2006。
J. Warnatz, U. Maas, R. W. Dibble, Combustion: Physical and Chemical Fundamentals, Modeling and Simulation, Experiments, Pollutant Formation, 4th ed., Springer, 2006.
独立核验依据 · Independent verification: 核验依据 1 ARCHIVE 标识 combustionphysic0000warn_v4e1：Combustion : ph
#燃烧化学 #化学发光 #烟黑 #预混火焰
同样点燃氢氧混合气，有时猛烈爆炸，有时却只缓慢氧化，由此形成的爆炸极限该如何用链支化机理来解释？
Igniting a hydrogen-oxygen mixture sometimes triggers violent explosion and sometimes only slow oxidation; how can the resulting explosion limits be explained by chain-branching kinetics?
关键在于自由基增殖与销毁之间的竞争。H• + O2 -> OH• + O•这类支化步骤一次性翻倍活性粒子；低压时自由基易扩散到器壁复合，高压时三体碰撞（H + O2 + M）又将它们消灭，只有在中间的压力窗口内支化胜出，自由基雪崩式增长引发爆炸。温度与压力会移动这一平衡，于是出现下限与上限。
The decisive factor is the race between radical multiplication and radical removal. Branching steps such as H• + O2 -> OH• + O• double the active population at a stroke; at low pressure radicals diffuse to the walls and recombine, while at high pressure three-body collisions (H + O2 + M) destroy them. Only in an intermediate pressure window does branching win, producing an explosive radical avalanche; shifts of this balance with temperature and pressure define the lower and upper limits.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
C.K. Westbrook & F.L. Dryer, Progress in Energy and Combustion Science, 1984, 10, 1-57
C.K. Westbrook and F.L. Dryer, Prog. Energy Combust. Sci., 1984, 10, 1-57, DOI: 10.1016/0360-1285(84)90118-7
独立核验依据 · Independent verification: 核验依据 1 CROSSREF 标识 10.1016/0360-1285(84)90118-7：Chemical kineti
#链支化 #爆炸极限 #自由基动力学
为什么黑火药一硝二硫三木炭能爆炸？
Why does black powder (saltpeter, sulfur, charcoal) explode?
硝酸钾供氧，木炭作燃料，硫降低燃点并增加产气；三者混合点燃瞬间生成大量二氧化碳和氮气，体积骤然膨胀而爆。
Potassium nitrate supplies oxygen, charcoal is fuel, sulfur lowers ignition temperature and adds gas; rapid combustion yields huge volumes of CO2 and N2, causing explosion.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#火药 #爆炸 #氧化还原
什么是燃烧焓？
What is enthalpy of combustion?
标准燃烧焓指 1 mol 物质在标准状态下完全燃烧生成稳定产物（如 CO₂(g)、H₂O(l)）时的焓变，通常为负值（放热）。它是评价燃料能量含量的指标。
Standard enthalpy of combustion is the enthalpy change when 1 mol of a substance burns completely to stable products (e.g., CO₂(g), H₂O(l)) under standard conditions; it is usually negative (exothermic) and measures fuel energy content.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
傅献彩 等,《物理化学》第5版,高等教育出版社,2005
Fu Xiancai et al., Physical Chemistry, 5th ed., Higher Education Press, 2005
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9787040167696（按标识回读: 物理化学(第五版)上册）
#燃烧焓 #热化学 #燃料