Why is the boiling point of water significantly greater than that of other group 6 (16) hydrides?

Water exhibits hydrogen bonding between neighbouring molecules, where other group 6 hydrides are held together by much weaker (ca. 10 x) Van Der Waal's forces of attraction. Waters hydrogen bondong ability arises from the presence of a highly electronegative oxygen atom in it's structure. Due to oxygen's propensity to attract negative charge, the shared electron between oxygen and hydrogen in each of the two bonds in water lies closer to the nucleus of oxygen than that of hydrogen. This results in a partially negatively charged oxygen atom and two partially positively charged hydrogen atoms. The partial charges can interact wih the opposite partial charge on a neighbouring molecul, forming a so called 'hydrogen bond.'

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