Electron Configuration and Valence Electrons. The electrons in an atom fill up its atomic orbitals according to the Aufbau Principle; Aufbau, in German, means building up..ach element has a number of valence electrons equal to its group number on the Periodic Table. This table illustrates a number of interesting, and complicating, features of electron configuration. Figure %: The periodicity of valence electrons. First, as electrons become higher in energy, a shift takes place.
I took the pregnancy test early at 2 & 3 weeks pregnant, and it came up negative twice. Yet I could feel something was different about my body, even though I had my cycle it fell short a few days, and was very light. Afterwards, I had breast tenderness, and dizziness.
A pregnancy test will detect this hormone about one week after fertilization. Most women tend to wait to take a pregnancy test until after they have missed one menstrual period. If you take a pregnancy test one week after you were supposed to get your period, the result will be about 95% accurate. If you take it too soon after fertilization, it may show up negative when in fact you really are pregnant. Pregnancy test are meant to be considered screening tests. If your test comes up negative, but you are experiencing symptoms of pregnancy you should call your doctor.