a specific size, sodium metal in the form of a solid block is introduced to the hollow part of the stem portion, and a protective agent made from solid paraffin or naphthalene is also introduced to the hollow part of the stem portion such as to form a barrier between the sodium metal ...
1. What can we know about sodium in paragraph 1? A.It is a kind of hard metal. B.Seawater contains plenty of sodium. C.It is able to power much-improved batteries. D.The most common battery today has been made of it. 2. How is the third paragraph developed ...
A process for the preparation of a desired chemical compound in a continuous reactor in which a part of the product stream exits the reactor and part of the product stream is recycled around the reactor in order to reduce the amount of buffer that would otherwise be required.图片...
Pure substances: Pure substances are made from only one type of particles and a constant structure. The properties or the chemical composition of the pure substances remain the same throughout. Answer and Explanation:
A. iron B. sodium C. oxygen D. hydrogen 相关知识点: 试题来源: 解析 A。铁是过渡金属元素。钠是碱金属元素,氧是非金属元素,氢是非金属元素。 1. 确定句子主语: 句子的关键词是“ice cream”, 所以主语是“an ice cream”。 2. 确定句子谓语: 句子描述的是“ice cream”的状态,所以谓语动词是“is”...
- One of the primary industrial applications of the heat generated from hydrogen combustion is in the oxy-hydrogen torch. - An oxy-hydrogen torch uses a mixture of hydrogen and oxygen gases to produce a flame that reaches very high temperatures (around 2800°C or 5072°F). ...
Notes: * A substance that satisfies either or both of the following conditions is treated as impurity and not "Intentionally added": a) One contained in a natural material, which cannot be completely removed in a refining process by adequate technical means (i.e. natural impurities); and b)...
On the other hand, upon acidification, the alkaline mixture X yields a solid M (C8H8O2) which gives rapid effervescence with aqueous sodium carbonate. Oxidation of M yields one of the monomers that is used to make Terylene. Terylene Deduce the structures of J, K, L and M, explaining ...
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The subject matter of the invention also comprises a method for the production of compounds of the general formula I (s = 2) or of their open ring forms (IB), which is characterized in that the compound of the general formula II or its open ring form (IIB) or a mixture of these bot...