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For the carbon, we start with 4 valence electrons, we have 0 lone pair electrons minus 4, and we end up with a formal charge of 0.
对于碳，我们从四个价电子开始，我们有零个孤对电子，再减去四，最终我们有零个形式电荷。
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So we're just subtracting, in effect, zero, right, from the enthalpy of the product, but of course it's important have that established because the heat of formation is something you could measure, right?
所以从效果上说，我们只是，从生成物的焓中减去了零，但，是确立这一点很重要,因为生成热是,你能测量的东西，对吧？
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They subtract this from the purchase price of the house and then you've got the cash to go and buy another house.
他们从售房价格里减去这个贷款余额,然后你就可以得到现金去买另一个房子
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For the sulfur, we start off with 6 valence electrons, minus 4 lone pair electrons, minus 2, taking in account our bonding electrons, so we end up with a formal charge of 0.
对于硫，我们从六个价电子开始，减去四个孤对电子，再减去二，算上我们的成键电子，因此最终我们有零个形式电荷。
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There you are at the pearly gates and you look back on your life and you could, in principle, add up all the pleasures, add up all the pains, subtract the pains from the pleasures and ask yourself, "How good a life did I have?
当你站在天堂门口回顾一生时,你可以，在原则上，累加所有快乐，累加所有痛苦，从快乐中减去痛苦然后问自己，“我的一生到底有多好？
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It says find the midpoint, which says, last take the start, which is pointing to that place and add it to start. And that basically, somewhere about here, gives me the midpoint.
先找到中点，从起点开始，指向这个位置，用first减去,加上得到偏移量），大概在这里，我们找到了终点。
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The ionization energy must then be nothing more than, that is the energy to go from the ground state here to n equals infinity, so that would be the energy at state infinity minus the energy of the ground state.
这个电离能一定不会大于，从基态到n为无限大时的能量,而是等于,无限远处的能量减去基态能量。
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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。
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And if we talk about chlorine, and both of the chlorines are the same in this case, we start with a valence number of 7 for chlorine, and then we subtract 6, because it had 6 lone pair electrons around each of the chlorine atoms.
而如果我们讨论氯的话，在这个例子中两个氯的情况都是一样的，从七个价电子开始，然后减去六，因为每个氯原子周围,都有六个孤对电子。
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If we go to the oxygen atom, now we're talking about starting with 6 in terms of valence electrons again, but instead of 2, you can see we have 6 lone pair electrons around the oxygen minus 1/2 of 2, so we have minus 1 is our formal charge.
如果我们分析氧原子的话，现在我们讨论的还是,从六个价电子开始，但孤对电子不再是两个了，你会看到氧周围,有六个孤对电子，再减去二的一半，因此我们有一个负的形式电荷。
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And then if we think about 3 s, 0 we want to start with 3, we subtract 1, again l is equal to 0, so minus and we have two radial nodes.
我们从3开始，减去，同样的l等于，所以减去0，我们有两个节点，这应该。
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You want to subtract off the value of a perpetuity that starts after 2T, six-month intervals, so this is the present value of the perpetuity that starts after 2T, six-month intervals.
所以就要从永续债券价格里减去,2T期以后,每六月一期券息的贴现值,这部分是永久债券从第2T期后,每半年一期券息的现值
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So, if we start instead with talking about the energy levels, we can relate these to frequency, because we already said that frequency is related to, or it's equal to the initial energy level here minus the final energy level there over Planck's constant to get us to frequency.
如果我们从讨论能级开始，我们可以联系到频率上,因为我们说过频率和能量相关,或者说等于初始能量,减去末态能量除以普朗克常数。
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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。
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