In a covalent bond one atom can attract the shared electrons more strongly than the other atom can. Water or H2O has a covalent bond whose Oxygen atoms attract more electrons that its Hydrogen atom. Since electrons have a negative charge, the Oxygen atom has a partial negative charge and the Hydrogen atom has a partial positive charge. These partial charges are what make water a polar molecule.marrit <span>· 2 years ago</span>
Recorded by a seismograph.
You can't usually just use a single spectrum line to confirm the identity of an element because there are cases that the emission line id not clearly defined. When the emission line is very weak compared to surrounding noise, in which case the more datapoints you have to build up confidence for the existence of a particular emission spectra, the better.
