सच्याउंन आधानिक परियोडिक तालिका सफल भयो वा भएन, मूल्याङ्कन गनुहोस् List out two demerits of Mendeleev's period table. Analyses modern penodic
table is able to overcome these dements or not.
दिदाको तालिका अध्ययन गरी सोधिएका प्रश्नहरुका उत्तर लेख्नुहोस्​

Explanation:

Mendeleev's period table

Ch4 and ph3 are both covalent since they are composed both of non-metals.    ch4 is non- polar because of  london forces and has a geometry of tetrahedral  ph3 , on the other hand, is umbrella shaped polar and has dipole-dipole intermolecular force (imf) . since ph3 is polar, it has a stronger imf