Mendeleev classified elements based on atomic weight, while the modern periodic table uses atomic number. Which anomaly in Mendeleev's table was directly resolved by this change?
Placement of noble gases
Position of tellurium and iodine
Existence of isotopes
Lanthanide contraction
Related Questions
Which of the following set of elements cannot be a triad
A) (7, 15, 31)
B) (40, 80, 120)
C) (14, 16, 18)
D) (19, 39, 59)
Which element's properties did Mendeleev accurately predict before its discovery, calling it 'eka-silicon'?
Gallium
Scandium
Germanium
Selenium
One limitation of Mendeleev's periodic table was its inability to perfectly accommodate:
Noble gases
Alkali metals
Halogens
Isotopes
In Mendeleev's periodic table, elements in the same group had similar:
Atomic weights
Atomic numbers
Chemical properties
Number of neutrons
If Mendeleev had known about the concept of isotopes, how would his periodic table have been different?
Isotopes of the same element would have been placed in different groups
Isotopes of the same element would have occupied the same position
The table would have been organized based on neutron number
The concept of periodicity would have been discarded
The statement that is true for the long form of the Periodic Table is
It reflects the order of decreasing atomic weights
It reflects the order of increasing atomic numbers
It reflects the order of increasing atomic radii
It reflects the order of increasing ionization energy
Mendeleev placed some elements with higher atomic weights before elements with lower atomic weights. This was done to:
Follow alphabetical order
Account for undiscovered elements
Maintain the periodicity of chemical properties
Reflect the abundance of elements
Which of the following pairs of elements would have been placed in the SAME group in Mendeleev's periodic table but DIFFERENT groups in the modern periodic table?
Tellurium (Te) and Iodine (I)
Sodium (Na) and Potassium (K)
Calcium (Ca) and Magnesium (Mg)
Iron (Fe) and Cobalt (Co)
Eka aluminum and Eka silicon are known as
Ga and Ge
Al and Si
Fe and S
N and Mg
Mendeleev left gaps in his periodic table. Which of the following elements was predicted by Mendeleev and later discovered, fitting into one of these gaps?
Sodium
Potassium
Calcium
Gallium
