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because,he predicted some possible chemical formulas of the then undiscovered elements between the elements in his periodic table. so he concluded that more elements with specific properties would be discovered.
Because he knew from his already discovered periods and groups of elements that the gaps would be filled by newly discovered elements. If you have a gap such as this, 3d5__3d7 along a period's outer valance level you can predict, which Mendeleev did, that the element with the outer valance number, 3d6, will be found in the future.
He predicted that elements with the predicted properties would be discovered to fill in these gaps.
Yes, Dimitri Mendeleev did (accurately, I might add) predict where elements would appear in his table. He also correctly predicted some of the missing elements' properties, based on where they were positioned in his table.
The reason that Mendeleev didn't make any predictions about the gases was that these gases were not even discovered yet, therefore it was impossible for Mendeleev to make predictions.----Dmitri Mendeleev made his predictions on what would fill the gaps on his far from perfect periodic table. He predicted their sizes, weights, appearances, etc.I think the reason he didn't make predictions is because noble gases are not visible, and weightless.-------------------------------Mendeleev couldn't predict the noble gases' properties because their existence wasn't known, as implied above.Argon, a noble gas, was noticed twenty-five years later by John William Strutt and Sir William Ramsey (the names are not really important).It doesn't matter that the elements weren't discovered. That's the whole point of arranging the elements. To PREDICT the properties of the missing/unknown ones.
U should know this.
because,he predicted some possible chemical formulas of the then undiscovered elements between the elements in his periodic table. so he concluded that more elements with specific properties would be discovered.
Because he knew from his already discovered periods and groups of elements that the gaps would be filled by newly discovered elements. If you have a gap such as this, 3d5__3d7 along a period's outer valance level you can predict, which Mendeleev did, that the element with the outer valance number, 3d6, will be found in the future.
He predicted that elements with the predicted properties would be discovered to fill in these gaps.
Yes, Dimitri Mendeleev did (accurately, I might add) predict where elements would appear in his table. He also correctly predicted some of the missing elements' properties, based on where they were positioned in his table.
Mendeleev left gaps in his table to place elements not known at the time. By looking at the chemical properties and physical properties of the elements next to a gap, he could also predict the properties of these undiscovered elements. For example, Mendeleev predicted the existence of 'eka-silicon', which would fit into a gap next to silicon. The element germanium was discovered later. Its properties were found to be similar to the predicted ones and confirmed Mendeleev's periodic table.
The reason that Mendeleev didn't make any predictions about the gases was that these gases were not even discovered yet, therefore it was impossible for Mendeleev to make predictions.----Dmitri Mendeleev made his predictions on what would fill the gaps on his far from perfect periodic table. He predicted their sizes, weights, appearances, etc.I think the reason he didn't make predictions is because noble gases are not visible, and weightless.-------------------------------Mendeleev couldn't predict the noble gases' properties because their existence wasn't known, as implied above.Argon, a noble gas, was noticed twenty-five years later by John William Strutt and Sir William Ramsey (the names are not really important).It doesn't matter that the elements weren't discovered. That's the whole point of arranging the elements. To PREDICT the properties of the missing/unknown ones.
Ekasilicon was the name appointed by Mendeleev to the undiscovered germanium; germanium has similar chemical properties to silicon and tin.
Mendeleev was able to predict the properties of the yet unknown element (Germanium) by the properties of the surrounding known elements on his periodic table of the elements. Predicting properties such as reactivity, density, atomic mass, etc., he knew where the undiscovered element would be placed.
Mendeleev named the missing elements after elements in the same group. he gave the name eka-aluminum to the element that belonged one space below aluminum on the able. Mendeleev predicted that eka-aluminum would be a soft metal with a melting point at a density of 5.9 g/cm3. In 1875,a french chemist discovered a new element. He named the element gallium in honor of France. Gallium is a soft metal with a melting point of 29. degrees Celsius and a density o f5.91 g/cm3. So pretty much in short Mendeleev left blank spaces because of Gallium.
The validity of the periodic table of elements, which was originally devised by Mendeleev, has been confirmed by a vast body of chemical research. It would not be an exaggeration to say that everything in the science of chemistry conforms to Mendeleev's theory.
mandeleev didn't know spaces in the Periodic Table because he doesn't arrange it john Kepler arrange it most of mendeleev discoveries of elements are few most of other element where discover by other scientist after him in 19th century