So what that means is that's how much energy we would have to put into a hydrogen molecule in order to get it to split apart into its two atoms.
它的意义,就是我们需要向一个氢分子中注入这么大的能量,才能将它分解成两个独立的原子。
to put in place policies that incentivizes people to use things such as energy efficiency
他们制定了一些政策,鼓励人们使用能效高的产品,
If we have a higher z effective, it's pulled in tighter, we have to put in more energy in order to eject an electron, so it turns out that that's why case 2 is actually the lowest energy that we need to put in.
而如果有效核电量更高,原子核的束缚也就更紧,我们不得不输入更多的能量来打出一个电子,这就是第二种情况,所需要输入的,能量更少的原因。
He preserved the broad concept of energy levels but put in some fine structure.
他继承了波尔的广泛意义上的能级概念,但引进了一个新的结构。
The z effective is lower, so we have to put less energy in to get an ion out.
它的有效核电量更低,所以我们只需要更少的能量就能打出一个离子。
So, you can imagine, that we'll actually probably have a lot of kinetic energy left over if we put a lot of energy in in the first place.
因此,可以想象,如果我们一开始,就注入大量的能量,那么得到的动能也应该很大。
I have got to put that in because that is a repulsive energy and that is going to decrease the energy of the system.
我必须要说清楚,因为这是一个排斥能,这将要减少这一系统的能量。
What we've learned so far is as a first approximation, what we want to do is put the atom with the lowest ionization energy in the middle here.
我们之前所学的可以作为第一近似,我们要做的是把电离能,最低的原子放在中间。
At this point, we have no other choice but to double up before going to the next energy level, 2px so we'll put a second one in the 2 p x.
在这点上我们没有其他选择,而只有双倍填充,在到下一个能级之前,所以我们放入第二个电子至。
This means in order to do that we actually have to put 7 kilojoules per mole of energy into the reaction to make it happen.
这意味为了完成上面的反应,我们不得不往里面注入,7,千焦每摩尔的能量。
So, thinking about ionization energy, which atom would you put in the middle here?
那么,从电离能的角度考虑,大家会把哪个原子放在中间?
So, if we want to go from that stable state to that less stable state, we need to put in a certain amount of energy to our system, that difference between the free electron and the electron bound to the metal.
所以,如果我们想使电子,从稳态到达不够稳定的状态,我们需要引入一定数量的,能量到系统中,即自由电子和束缚于金属的,电子的能量差。
So what we're doing is filling in those eight electrons following the Aufbau principle, so our first electron is 1s going to go in the 1 s, and then we have no other options for other orbitals that are at that same energy, 1s so we put the second electron in the 1 s as well.
它会是什么样子呢,我们正在做的是将这8个电子按照奥弗,堡原理进行填充,所以我们第一个电子将会进入,然后我们没有其他的,轨道的选择在同一个能级,所以我们把第二个电子也放入。
putting all those things together, if you looked at this question again we'd get 100% on it, 0 9 that our only option here is 0. 9, and that it's not the negative, it's the positive version, because we're talking about how much energy we have to put into the system in order to eject an electron.
把这些放在一起,你们再看一下题目,大家100%都能选对,我们唯一的选择就是这个,它不是负数,它是正的,因为我们说的,是要,把电子激发出来,需要提供的能量。
So you don't want to put in a negative energy, that's not going to help you out, you need to put in positive energy to get an electron out of the system. So that's why you'll find binding energies are always negative, and ionization energies are always going to be positive, or you could look at the equation and see it from there as well.
因为这对电离没有帮助,你需要一个正的能量,使得电子脱离这个系统,这就是为什么你会发现,结合能总是负的而电离能总是正的,或者你们看这个方程也可以发现这一点。
The reason it's aluminum is because aluminum has a lower z effective, so it's not being pulled in as tightly by the nucleus, and if it's not being pulled in as tightly, you're going to have to put in less energy in order to ionize it, so that's why it's actually going to have the smaller ionization energy.
原因是,铝的有效核电量更少,所以没有被原子核束缚得更紧,而如果没有被束缚得更紧,你为了电离它所需要注入的能量也就更少,这就是,它的电离能会更低的原因。
Often a good thing to start with is to put the lowest ionization energy atom in the middle, and if you don't have charge separation then go with that structure, but if you do find you have a lot of separation, such as the case in negative 2, positive 2, and minus 1, then you want to say wait a second, this is really bad in terms of formal charge, let me go ahead and see what other options I have here.
通常一开始把电离能最低的原子,放在中心位置就很好了,如果你发现电荷没有分开,那么这个结构就没问题了,但是如果你发现有很多分开的电荷,比如这种情况,有负二,正二和负一,那么你会想要说等一下,从形式电荷来看这很不好,让我去看看其它可能的选择。
In terms of picking a Lewis structure that's going to be the lowest energy, what you want to do is put the atom with the lowest ionization energy in the center of your atom.
为了挑选一个具有,最低能量的路易斯结构,你需要把电离能最低的原子,放在最当中的位置。
I am going to put energy in the following manner.
我会这样讲解能量问题。
So, for example, in a hydrogen atom, if you take the binding energy, the negative of that is going to be how much energy you have to put in to ionize the hydrogen atom.
例如在氢原子里面,如果你取一个结合能,它的负数就是。
So, which has the smallest energy that you have to put in in order to eject this electron?
也就是,哪一项为了打出一个电子,所需要注入的能量最少?
So if we can figure out the binding energy, we can also figure out how much energy we have to put into our atom in order to a eject or ionize an electron.
所以如果我们可以计算出结合能,我们也可以计算出,我们需要注入多少能量到原子中,去逐出或电离一个电子。
This intuitively should make a lot of sense, because we know we're trying to minimize electron repulsions to keep things in as low an energy state as possible, so it makes sense that we would put one electron in each orbital first before we double up in any orbital.
这个直观上讲得通,因为我们知道尝试去最小化电子排斥力,从而尽可能的保持处于一个较低的能态,所以它讲得通,在我们在同一个轨道放入两个电子之前,我们首先把电子放入每一个轨道。
Remember, because that 1 s orbital is all the way down in terms of if we're thinking about an energy diagram, we're all the way down here, so we have a huge amount of energy we have to put into the system in order to eject an electron.
还记得吧,因为1,s,轨道在能量示意图里,是在最底部的,我们要一直到最下面,所以我们要向这个系统注入非常大的能量,才能打出一个电子。
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