1. **金属与酸的反应** - **反应方程式及现象(以常见金属镁、铁、锌、铝与稀硫酸反应为例)** - 镁与稀硫酸反应:\(Mg + H_{2}SO_{4}=MgSO_{4}+H_{2}\uparrow\),现象为反应剧烈,有大量气泡产生。 - 铁与稀硫酸反应:\(Fe + H_{2}SO_{4}=FeSO_{4}+H_{2}\uparrow\),现象是有气泡产生,溶液由无色变为浅绿色(因为生成了亚铁离子)。 - 锌与稀硫酸反应:\(Zn + H_{2}SO_{4}=ZnSO_{4}+H_{2}\uparrow\),反应较剧烈,产生气泡。 - 铝与稀硫酸反应:\(2Al+3H_{2}SO_{4}=Al_{2}(SO_{4})_{3}+3H_{2}\uparrow\),产生气泡。 - **反应规律及图像问题(针对初中化学常见考点)** - 当等量的金属分别和足量的酸反应(酸过量)时,反应中最终产生氢气的多少由金属决定。在金属化合价相同的情况下,对于相同质量的金属,金属的相对原子质量越大,生成的氢气越少;生成的氢气越多,金属的相对原子质量越小。 - 当等量的酸分别和足量的金属反应(金属过量)时,反应产生氢气的量由酸的量决定,最终产生氢气的量相等。 - 两种或多种金属与稀酸反应时,反应的快慢(即相同时间内产生氢气的多少)由金属的活动性决定,在温度、金属颗粒大小和稀酸溶液溶质质量分数一定的条件下,金属的活动性越强,生成氢气就越快;生成氢气越快,说明金属的活动性就越强。在图像中,纵坐标通常为产生氢气的量,横坐标可能为时间、消耗酸的质量或消耗金属的质量。 2. **金属与盐溶液的反应** - **反应方程式及现象(以铁丝浸入硫酸铜溶液为例)** - 反应方程式:\(Fe + CuSO_{4}=FeSO_{4}+Cu\),现象为浸入溶液中的铁钉表面覆盖红色物质(铜),溶液由蓝色逐渐变为浅绿色。 - **反应条件及规律** - 金属(钾、钙、钠除外)的活动性强于盐中金属阳离子对应的金属;盐必须可溶于水。当多种金属和多种盐溶液反应时,最活泼的金属先与最不活泼的金属盐反应,再轮到较活泼的金属或金属盐反应。例如向一定量的硝酸银和硝酸亚铁混合溶液中加入锌粉,金属活动性顺序为锌>铁>银,锌先与硝酸银反应,硝酸银完全反应后,若锌还有剩余,则锌再与硝酸亚铁反应。 3. **金属与酸性溶液中的氢离子反应(以酸性溶液与金属反应为例)** - 酸性溶液中的氢离子(\(H^{+}\))会与金属发生反应,如形成氢气,同时金属逐渐溶解,但未明确具体金属时无法给出确切方程式。 4. **特殊金属与溶液反应(如金属铋与稀硝酸反应)** - 放入金属铋,加入稀硝酸,加热试管,冷却后加水稀释,反应方程式为\(Bi + 4HNO_{3}=Bi(NO_{3})_{3}+NO\uparrow+2H_{2}O\)(根据给出的后续反应推测铋与稀硝酸反应的可能方程式),现象未明确提及,可能有气体产生等现象。 5. **金属与水反应(以金属钾与水反应为例,虽然未明确要求,但属于金属与溶液相关反应类型)** - 金属钾与水反应:\(2K + 2H_{2}O = 2KOH+H_{2}\uparrow\),现象是反应剧烈,可能有燃烧、爆炸等危险现象(因为反应放出大量热和氢气)。 点击前往免费阅读更多精彩小说
There is no chemical reaction between NaCl2 and magnesiumcarbonate2. In chemistry, the conditions for metathesis reactions to occur were the formation of precipitations, gases, or water. After mixing the two, the conditions for the metathesis reaction were not met, so there was no reaction, no reaction equation, and no reaction phenomenon. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
For the reaction between sulfur and metal, the following are the common reactions and situations: - Sulfur and iron reaction: The chemical equation is: FeS + S = (heating)FeS. This reaction does not involve free moving ions, so it cannot be rewritten as an ion equation. The phenomenon was the formation of black solid iron Sulphide. - Sulfur and copper reaction: The chemical equation is 2Cu + S = (heating) Cu2 S. Similarly, the ion equation cannot be written. The phenomenon was the formation of black cuprous sulfur solid. - Sulfur and Na reaction: The chemical equation is 2Na + S =(grinding)Na <2> S. There is no need to rewrite the ion equation. The phenomenon was that during the grinding process, a violent reaction formed a white solid of sulfur dioxide. - Sulfur and aluminum reaction: The chemical equation is 3S +2AI = Al2S, which cannot be rewritten as an ion equation. The reaction phenomenon was the formation of aluminum sulfur solid. - Sulfur and mercury reaction: The chemical equation is as follows: Mercury + S = HgS, which cannot be written as an ion equation. The reaction phenomenon is the formation of black mercury sulfur solid. In general, since most of these reactions were solid-state reactions or did not carry out the ionisation process in the solution system, there was basically no ion equation. Most of the reaction phenomena were the formation of the corresponding sulfur solid, and the color of the solid was different. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
There was no reaction between the saturated solution of NaCl2 and the solution of NaOx. This was because it did not meet the conditions for a metathesis reaction (forming a deposit, gas, or water). <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Mercury reacts with oxygen under heating conditions to form mercury dioxide. The chemical equation is [2Mercury + O_{2}]{=[2Mercury + O_{2}]}{=[2Mercury + O_{2}]}{=[2Mercury + O_{2}}}}{=[2Mercury + O_{2}}}{=[2Mercury + O_{2}}}}{=[2Mercury + O_{2}}}{=[2O_{2}}}} 2HgO\)。 The reaction was the appearance of a large amount of white smoke. From the nature of the reaction, mercury was a chemical element with the element symbol <anno data-annotation-id ="00000000 - 4000 - 4000 - 8000 - 9000 - 80000000000"></anno>. It was located in the sixth cycle of the periodic table of chemical elements, Group III. It was a metal that existed in liquid form at room temperature and pressure. Its electron configuration allows the two electrons on the 6s sub-level to have extremely high orbital speeds, about 58% of the speed of light, which causes the mass of the electron to increase by 23% through the relativistic effect. The increase in the mass of the electron reduces the orbital radius, and mercury almost does not contribute its own electrons to form metal bonds. Mercury atoms attract each other mainly through van der Waals forces (this force is very weak). When heated, mercury reacted with oxygen to form mercury dioxide. Due to the change in the state of the substance during the reaction and the formation of the product, a large amount of white smoke appeared. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
There is no chemical reaction between the two of them. In terms of chemical principles, the conditions for the metathesis reaction to occur were the formation of precipitations, gases, or water. The mixture of the two did not meet the conditions for the metathesis reaction to occur, so there would be no reaction. Therefore, there was no reaction equation, reaction phenomenon, and phenomenon analysis. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The chemical equation of the reaction between hydrogen and Cl2 was H ^+ Cl2 = 2HQ (Condition: Illumination or ignition). [Phenomenon: When hydrogen and Cl2 react, if it burns quietly, it will emit a pale flame, and there will be white fog at the mouth of the gas collector. If hydrogen and Cl2 are mixed and illuminated, it will explode.] <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The chemical equation for the reaction between sulfur and oxygen is: S + O2 SO_2\)。 The reaction phenomenon was: burning in the air to produce a light blue flame, releasing heat and producing a gas with a pungent smell; burning in oxygen to produce a bright blue-purple flame, releasing heat and producing a gas with a pungent smell. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
It was very difficult for the reaction between the two solutions to occur, and there was no reaction equation. Due to the existence of p-pi in the double bond, the C-Clbond length was shortened and the bond energy was increased. It was difficult for the Cl-atom to leave, so it was difficult to react with the silver nitrates. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
1. **硫与铁反应** - 方程式:\(Fe + S \stackrel{\triangle}{=\!=\!=} FeS\)(硫化亚铁,黑褐色) - 现象:反应剧烈,生成黑褐色固体。 2. **硫与铜反应** - 方程式:\(2Cu+S \stackrel{\triangle}{=\!=\!=}Cu_{2}S\)(硫化亚铜,黑色) - 现象:有黑色固体生成。 3. **硫与汞反应** - 方程式:\(Hg + S=\!=\!= HgS\)(硫化汞,黑色) - 现象:常温下迅速反应,生成黑色固体。 4. **硫与氢气反应** - 方程式:\(H_{2}+S \stackrel{点燃}{=\!=\!=}H_{2}S\) - 现象:有臭鸡蛋气味的气体生成。 5. **硫与氧气反应** - 方程式:\(S + O_{2}\stackrel{点燃}{=\!=\!=}SO_{2}\) - 现象:有刺激性气味的气体生成。 6. **硫与热的碱溶液反应** - 方程式:\(3S + 6NaOH \stackrel{\triangle}{=\!=\!=}2Na_{2}S+Na_{2}SO_{3}+3H_{2}O\)(离子方程式为\(3S + 6OH^{-}\stackrel{\triangle}{=\!=\!=}2S^{2 -}+SO_{3}^{2 -}+3H_{2}O\)) - 现象:无明显特殊现象(溶液中的反应,反应后溶液成分发生改变)。 <a href="/?from=ask_words" style="color:red" target="_blank">点击前往免费阅读更多精彩小说</a>
If the two did not react, the reaction equation could not be written. carbon dioxide (CO2) was a non-metallic oxide-like substance, while Cl2 was a non-metallic elemental substance. A substitution reaction occurred between the compound and the elemental substance. However, this kind of reaction required the compound to be a dissolved metal compound or acid, while CO2 was a non-metal compound, which did not meet the conditions, so the two did not react. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>