Yttrium barium copper oxide (YBa2Cu3O7) is a famous crystalline material ever discovered in the world of quantum physics. It becomes a superconductor when it is exposed to liquid nitrogen. Calculate the mass percentage of yttrium, barium, copper, and oxygen in this compound.
Correct answer: A. Y = 13%, Ba = 41%, Cu = 29%, O = 17%
- A. Y = 13%, Ba = 41%, Cu = 29%, O = 17%
- B. Y = 17%, Ba = 39%, Cu = 23%, O = 21%
- C. Y = 15%, Ba = 52%, Cu = 10%, O = 23%
- D. Y = 19%, Ba = 41%, Cu = 31%, O = 9%
Explanation
To find the mass percentage of each element in YBa₂Cu₃O₇, we need to first calculate its molar mass, which is:1(Y) + 2(Ba) + 3(Cu) + 7(O) = 1(88.91 g/mol) + 2(137.33 g/mol) + 3(63.55 g/mol) + 7(15.99 g/mol) = 666.96 g/molNext, we calculate the mass of each element in one mole of YBa₂Cu₃O₇:- Y: 88.91 g/mol x 1/mol = 88.91 g- Ba: 137.33 g/mol x 2/mol = 274.66 g- Cu: 63.55 g/mol x 3/mol = 190.65 g- O: 15.99 g/mol x 7/mol = 111.93 gFinally, we can calculate the mass percentage of each element as:- % Y = (88.91 g / 666.96 g) x 100% = 13%- % Ba = (274.66 g / 666.96 g) x 100% = 41%- % Cu = (190.65 g / 666.96 g) x 100% = 29%- % O = (111.93 g / 666.96 g) x 100% = 17%Therefore, the correct answer is A) Y = 13%, Ba = 41%, Cu = 29%, O = 17%.
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