你對電價數 缺乏基本概念
用CO2來說
o = c = o
因為氧(O) 的陰電性 3.0 高於 碳 2.5
因此當任何其中一邊 C=O 共用電子成為共價鍵 的時候
電子實際上不是平均的分享
電子會偏向 O 稍微遠離 C
所以會形氧帶有負電的傾向 -2
碳被電子遠離 因此會有帶偏正電 +4
回到問題
電價決定的時候要堅守規則
氧優先於碳
90% 以上氧都是 -2
因此答案如下
CO CO2 CO3
C +2 +4 +6
O -2 -2 -2
總電價 0 0 0
"只要是分子 也就是不是離子 一定就是電中性"
不是電中性的只有離子
高中教材來說 通常只能容在水中 或是其他液體
例如 NO3-
N +5
O -2
總電價 (+5 )*1 + (-2)*3 = -1
PS:
這題跟同位素完全無關
In
biology, one of the factors that defines a living thing from an inanimate object is the organism's ability to carry out
chemical reactions that are crucial for its survival. Even one-celled organisms are capable of hundreds of chemical reactions within their cell walls. Imagine the infinite amount of reactions that a large organism such as a human carries out. None of these reactions are possible without enzymes.
Enzymes are biological
catalysts or assistants. Enzymes consist of various types of proteins that work to drive the chemical reaction required for a specific action or nutrient. Enzymes can either launch a reaction or speed it up. The chemicals that are transformed with the help of enzymes are called
substrates. In the absence of enzymes, these chemicals are called
reactants.
To illustrate the speed and efficiency of enzymes, substrates can be transformed to usable products at the rate of ten times per second. Considering that there are an estimated 75,000 different enzymes in the human body, these chemical reactions are performed at an amazing rate. On the other hand, in the absence of enzymes, reactants may take hundreds of years to convert into a usable product, if they are able to do so at all. This is why enzymes are crucial in the sustenance of life on earth.
Generally, enzymes work on substrates in one of three ways:
substrate orientation, physical stress, and changes in substrate reactivity. Substrate orientation occurs when an enzyme causes substrate molecules to align with each other and form a
bond. When an enzyme uses physical stress on a substrate, it in effect grips the substrate and forces the molecule to break apart. An enzyme that causes changes in substrate reactivity alters the placement of the molecule’s electrons, which influences the molecule’s ability to bond with other molecules.
Enzymes have active sites where they come into contact with particular substrates. The catalytic properties of enzymes are a cyclic process. Once a substrate has come into contact with the active site of an enzyme, it is modified by the enzyme to form the end product. Once the process is complete, the enzyme releases the product and is ready to begin the process with new substrates. Enzymes are never wasted and always recycled.
The absence of enzymes is responsible for many diseases. In humans, a tragic disease called
phenylketonuria (
PKU), which causes severe mental retardation and even death in infants, is the result of the absence of one type of enzyme.
Tay-Sachs disease is a similarly tragic result of an
enzyme deficiency. It causes retardation, paralysis, and often death in early childhood when left untreated.
Our ability to alter enzymes by inhibiting their functioning abilities has resulted in hundreds of life saving drugs. One example is penicillin, a well-known
antibiotic that can cure syphilis,
pneumonia, and other illnesses. Penicillin works by bonding to the active sites of the disease-causing bacteria’s enzymes, ultimately destroying the bacteria’s ability to survive and reproduce.
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