The formula of the copper oxide would be [tex]Cu_2O[/tex]
Mass of copper sample = 7.298 g
Mass of final product after reacting with oxygen = 8.217
Mass of oxygen = 8.217 - 7.298
= 0.919 g
Mole ratios
Cu = 7.298/63.546
= 0.115
O = 0.919/16
= 0.057
Cu = 0.115/0.057
= 2
O = 0.057/0.057
= 1
Thus, the formula for the copper oxide will be [tex]Cu_2O[/tex]
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