QUESTIONS 1. What do the numbers on Mendeleev\'s periodic table represent? 2. Na
ID: 954291 • Letter: Q
Question
QUESTIONS 1. What do the numbers on Mendeleev's periodic table represent? 2. Name the chemical family of elements that is absent from Mendeleev's table. Use the modern periodic table to identify the four elements marked with question marks on Mendeleev's periodic table in page 2. 3. 4. What did the law of octaves state about the elements? Why was Mendeleev's decision to leave blank spaces on his table sometimes was referred to as his most significant contribution to the periodic table? S. 6. State the periodic law. How does this law differ from Mendeleev's arrangement of the periodic table?Explanation / Answer
1) The numbers on the Mendeleev's Periodic table represents the Atomic mass of the elements.
2) Noble gases family are absent from Mendeleev's Periodic table .
4) He state that if the chemical elements are arranged according to increasing atomic weight, those with similar physical and chemical properties occur after each interval of seven elements.
5) the gapes in the Mendeleev's Periodic table is significant because these gapes represents unknown elements . Later when these elements were discoverd their properties are found to be similar to those predicted by the Mendeleev
6) Periodic law state that the physical and chemical properties of the element are the periodic function of their atomic numbers .
while Mendeleev state that the physical and chemical properties of the element are the periodic function of their atomic mass
7) The elements present in the same group have the same number of electrons in the outer orbital .
8) dense gas means that first it has having higher molecular weight and it is a gas that means it is having weaker attraction forces
from above we can say they are found on right hand side of periodic table ( noble gas family ) and
Rn (Radon) is the densest .
9 the properties are of metals
1)High melting points
2)High densities
3) Large atomic radii
4)Low ionization energies
5)Low electronegativities,
6)Thermal conductors
7)Electrical conductors
10 . the most metallic element must be francium . (it is man made )
natural is ( cesium )