Also,the nation's overall unemployment rate was 10.2 percent in October, its highest level in 26 years.
VOA: standard.2009.11.12
I've just finished Level 2 Diploma on Design.
我刚刚完成了设计专业的二级学位。
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。
Last year, the SEC put out a proposal that -it's getting too easy to be an accredited investor -so they put out a proposal that we raise the wealth level to $2.5 million.
去年证交会发布了一项提议,鉴于合格投资者的门槛较低,因此他们提议,把准入门槛提高到250万美元
So anything that goes from a higher energy level to 2 is going to be falling within the Balmer series, which is in the visible range of the spectrum.
任何更高能级到2能级2,都是属于Balmer系,它在可见光谱中。
They're not going to want to add on another electron, because then it'll have to jump a very large energy level go from n equals 2, to n equals 3, and n equals 4, and so on.
它们不愿意增加另外一个电子,因为这会让它们跳到一个非常高的能级上去,依次是,n,等于,2,3,4,等等。
So, our next level up that we can go is going to be the n equals 2 energy level, but we also have an l and an m value, 0 so our lowest l is going to be a there.
所以下一个能量,是n等于2的能级,但我们还有l和m的值,所以我们最低的l等于。
So what we'll do is this problem here, which is let's calculate out what the wavelength of radiation n would be emitted from a hydrogen atom if we start at the n equals 3 level and we go down to the n equals 2 level.
我们来做这个问题,让我们来计算一下,从n等于3到,等于2能级氢原子辐射的波长是多少。
So this is our final equation, and this is actually called the Balmer series, which was named after Balmer, and this tells us the frequency of any of the lights where we start with an electron in some higher energy level and we drop down to an n final that's equal to 2.
把2代入到这里,所以得到1除以,这就是我们最终的方程,这叫做Balmer系,以Balmer名字命名的,它告诉我们从高能级掉到n等于2的,最终能级所发出光的频率。
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