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Mendeleev also predicted the oxide of eka-silicon…

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Mendeleev also predicted the oxide of eka-silicon. He gave it a density of $4.7\ \text{g/cm}^3$ . Germanium dioxide was later measured at $4.23\ \text{g/cm}^3$ . Find the percentage error of his prediction, as a share of the measured value.

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Mendeleev arranged the elements by atomic mass, in groups of similar properties. He left gaps and predicted the missing elements, such as eka-aluminium (gallium) and eka-silicon (germanium). Error of a prediction $= \dfrac{|\text{found} - \text{predicted}|}{\text{found}} \times 100\ \%$ .

The worked solution

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← The atomic masses of beryllium, magnesium and calcium are 9.0 u, 24.3 u and 40.1 u…Mendeleev left gaps in his table. Why was that important? … →

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Mendeleev also predicted the oxide of eka-silicon…

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