<p>Nitrogen has the electronic configuration&nbsp;<math xmlns="http://www.w3.org/1998/Math/MathML" class="wrs_chemistry"><mn>1</mn><msup><mi mathvariant="normal">s</mi><mn>2</mn></msup><mo>,</mo><mo>&#160;</mo><mn>2</mn><msup><mi mathvariant="normal">s</mi><mn>2</mn></msup><mn>2</mn><msubsup><mi mathvariant="normal">p</mi><mi mathvariant="normal">x</mi><mn>1</mn></msubsup><mn>2</mn><msubsup><mi mathvariant="normal">p</mi><mi mathvariant="normal">y</mi><mn>1</mn></msubsup><mn>2</mn><msubsup><mi mathvariant="normal">p</mi><mi mathvariant="normal">z</mi><mn>1</mn></msubsup><mo>&#160;</mo><mi>and</mi><mo>&#160;</mo><mi>not</mi><mo>&#160;</mo><mn>1</mn><msup><mi mathvariant="normal">s</mi><mn>2</mn></msup><mo>,</mo><mo>&#160;</mo><mn>2</mn><msup><mi mathvariant="normal">s</mi><mn>2</mn></msup><mn>2</mn><msubsup><mi mathvariant="normal">p</mi><mi mathvariant="normal">x</mi><mn>2</mn></msubsup><mn>2</mn><msubsup><mi mathvariant="normal">p</mi><mi mathvariant="normal">y</mi><mn>1</mn></msubsup><mn>2</mn><msubsup><mi mathvariant="normal">p</mi><mi mathvariant="normal">z</mi><mn>0</mn></msubsup></math>. It was proposed by:</p>