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sodium atom has one electron in its outer shell 2,8,1 and chlorine has seven electron in outer shell 2,8,7. therefore sodium losses one electron to be stable while chlorine gain one electron to be stable.this means its easy for sodium atom to lose one electron than to gain 7. and its also easy for chlorine atom to gain one electron than to loss 7. the form ionic bond
atom in water are both non metals that need to share electron to be stable. ie covenant bond
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