That's the set up. We're going to run the reactants, the reaction. The reactants are going to turn into products.
这就是我们的装置,我们要进行反应,让反应物变成生成物。
And we haven't talked about reactions at all yet, so you don't need to worry about the specifics of that exactly, but just that if you have this negative change in energy, you have a more stable product than you do reactant.
当然我们还没有开始讨论反应,所以你不用担心它的细节是怎么样的,你只需要知道,如果能量的变化是负值,那么你将得到一个比反应物更稳定的生成物。
That's the important message, delta H of formation of the products, minus delta H of formation of the reactants.
去反应物的生成焓,这,是个重要的信息,生成物的生成焓,减去反应物的生成焓。
How many moles of gas are there in each case, in reactants and products? If that changes, of course you know that the pressure in there is going to change at constant volume if the amount of gas in there is changing.
在反应物和生成物中,各有多少摩尔的气体?,如果它发生了变化,当然在等体条件下,如果气体的总量,发生了变化,压强也会发生变化。
It's a state function. If we know the enthalpy of the products minus the enthalpy of the reactants, right. It's a state function.
如果我们知道生成物的焓减,去反应物的焓的值,它是个态函数,原则上我们可以做到。
In other words, I've got reactants, and I've got products. What's delta H of reaction?
换句话说,我有了反应物,我有了生成物?
Right? In other words I've got the stoichiometric coefficients in there and the values, and I'm subtracting the reactants from products -1652kJ/mol wind up with minus 1652 kilojoules per mole.
对吧?换句话说这里我用了化学,计量系数和生成热的值,从生成物中减去反应物,最后得到。
In other words, we choose a convention for the zero of entropy, so that then we can write entropies of products and reactants always referring to the same standard state.
换句话说,我们选择了一个,焓零点的约定,这样我们,就可以总是相对于同样的标准,状态写出生成物和反应物的焓。
There is some mixture of them.
实际情况是生成物与反应物的混合。
We can tabulate them. We can know them, and then when we have reactions that inter-convert different compounds, we can calculate the heat of reaction is just the difference between the heat of formation of the reactants, and the heat of formation of the products, right.
种化合物的生成热,可以把它们列成表,可以认知它们,而当我们要处理,在不同化合物间转变的反应时,我们只要计算反应物和,生成物的生成热之间的不同,就能计算出反应热。
When delta G is zero, you know, it doesn't mean that you've got all of one side, all reactants and zero products or all products and zero reactants.
当dG等于零的时候,化学反应并不处在任何一边,例如全部都是反应物没有生成物,或者全部都是生成物而没有反应物。
It's delta H of formation of the products minus delta H of formation of the reactants.
反应的△H是多少?,它就是生成物的生成焓减。
So what we'll end up with is boron plus, 1 s 2 2 s 2 1 s 2, 2 s 2, E and what we say is the delta energy or the change in energy as the same thing as saying the energy of the products minus the energy of our reactant here, that's how much energy we have to put into the system to eject an electron.
所以结果应该是正一价的硼,电子排布为,我们说,Δ,也就是,E,的变化量,等于生成物的能量,减去反应物的能量,这就是我们从这个系统中,打出一个电子所需要的能量。
Of course, the cyclic steps that we've taken to do this apply not just for breaking down reactants and product into the elements in their standards states, but of course we could also look at whole sets of reactions and write cycles as well, right.
当然,我们这里用的循环的,步骤不仅仅在把生成物,和反应物拆成其标准状态下,的元素时有效,我们也可以研究整个一系列,反应并写出相应循环。
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