化学等式

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How do you make shrimp gumbo?
::你怎么做虾口香糖?

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Shrimp gumbo is one of many enjoyable dishes that are part of the Cajun culture in Louisiana. It’s a spicy dish that needs careful control of all the ingredients so that it has a “kick,” but is not overwhelming. Recipes tell not only what is in the preparation, but describes how much of each ingredient and details of how to cook the meal. Similarly, We need this type of information in order to carry out successfully and safely.
::虾口香糖是路易斯安那州卡琼文化中许多令人愉快的菜盘之一。 它是一种辣菜,需要小心地控制所有成分,这样它才能有一个“棒棒 ” , 但却不是压倒性的。 食谱不仅说明准备中的内容,而且说明每个成分的多少以及如何烹饪。 同样,我们需要这种信息才能成功和安全地进行。

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Chemical Equations
::化学等量

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are time-consuming to write and do not prove to be convenient for many of the things that chemists need to do with equations. A chemical equation is a representation of a chemical reaction that displays the reactants and products with chemical formulas. The chemical equation for the reaction of methane with oxygen is shown:
::化学方程式代表化学反应,显示反应器和产品与化学方程式。甲烷与氧反应的化学方程式显示:

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$$\begin{align*}\text{CH}_4+\text{O}_2 \rightarrow \text{CO}_2+\text{H}_2\text{O}\end{align*}$$
::CH4+O2+O2+CO2+H2O

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The equation above, called a skeleton equation , is an equation that shows only the formulas of the reactants and products with nothing to indicate the relative amounts. The first step in writing an accurate chemical equation is to write the skeleton equation, making sure that the formulas of all substances involved are written correctly. All reactants are written to the left of the yield arrow, separated from one another by a plus sign. Likewise, products are written to the right of the yield arrow, also separated with a plus sign.
::上述方程式称为骨架方程式,是一个只显示反应器和产品公式的方程式,没有显示相对数量。写出准确化学方程式的第一步是写出骨架方程式,确保所有所涉物质的公式都写得正确。所有反应器都写在产出箭头左侧,用加号分隔开来。同样,产品也写在产出箭头右侧,并用加号分隔开来。

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It is often important to know the physical states of the reactants and products taking part in a reaction. To do this, put the appropriate symbol in parentheses after each formula: ( s ) for solid, ( l ) for , ( g ) for , and ( aq ) for an aqueous (water-based) solution. The previous reaction becomes:
::要做到这一点,在每个公式后面的括号中加上适当的符号s) 固体,(l) 固体,(g) 水(水)溶液,(q) 溶液(水)溶液。

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$$\begin{align*}\text{CH}_4(g) + \text{O}_2(g) \rightarrow \text{CO}_2(g) + \text{H}_2\text{O}(l)\end{align*}$$
::CH4(g)+O2(g)+O2(g)+CO2(g)+H2O(l)

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Table shows a listing of symbols used in chemical equations. Some, such as the double arrow which represents equilibrium, and the use of a in a reaction, will be treated in detail in other concepts.
::表格显示了化学方程式中使用的符号列表。有些符号,如代表平衡的双箭头和反应中的使用,将在其他概念中详细处理。

Symbols Used in Chemical Equations

Symbol	Description
+	Used to separate multiple reactants or products
$\begin{align*}\rightarrow\end{align*}$	yield sign; separates reactants from products
$\begin{align*}\rightleftarrows\end{align*}$	replaces the yield sign for reversible reactions that reach equilibrium
( s )	reactant or product in the solid state
( l )	reactant or product in the liquid state
( g )	reactant or product in the gas state
( aq )	reactant or product in an aqueous solution (dissolved in water)
$\begin{align*}\overset{Pt}{\rightarrow}\end{align*}$	formula written above the arrow is used as a catalyst in the reaction
$\begin{align*}\overset{\Delta}{\rightarrow}\end{align*}$	triangle indicates that the reaction is being heated