Germanium had not yet been discovered when Mendeleev created his periodic table.
Table 1 shows some of the properties that Mendeleev predicted for this undiscovered element (which he named eka-silicon) alongside the actual properties of germanium.
| Property | Predicted property (eka-silicon) | Actual property (germanium) |
|---|---|---|
| Relative atomic mass | 72 | 72.6 |
| Density in g/cm3\text{g/cm}^3g/cm3 | 5.5 | 5.35 |
| Formula of oxide | EsO2\text{EsO}_2EsO2 | GeO2\text{GeO}_2GeO2 |
| Density of oxide in g/cm3\text{g/cm}^3g/cm3 | 4.7 | 4.7 |
Describe how Mendeleev predicted these properties of germanium before it was discovered.
80 exam-style questions on Edexcel GCSE Chemistry 2.2 The periodic table, covering 2.2.1 Mendeleev's periodic table, 2.2.2 Periods, groups, metals and non-metals, and 2.2.3 Electronic configuration and position in the periodic table. Each one has a worked solution and a mark scheme showing where the marks go.