In the modern periodic table, why does cobalt having higher atomic mass of 58.93 appear before nickel having atomic mass of 58.71?

Name the transition element having lowest atomic mass.

(i) The electronic configuration of an atom is [Z](n-2) f^(14)(n-1)d^(1)ns^(2) . What is the minimum position of the atom in the periodic table and correspondingly what is the atomic number of Z? (ii) Find the number of unpaired electrons in the atom of the element having atomic number 16. (iii) Which of the following ions does not obey Bohr's atomic theory? He^(2+),Li^(2+),B^(3+),Be^(3+) .

In modern periodic table, period indicates the value of (A) atomic number (B) atomic mass (C) principal quantum number ltbr. (D) azimuthal quantum number.

Write the IUPAC name of the compound (A) in which the molar rations of C,H , and O of equal having a molecular mass of 58

Write down the electronic configurations of the elements having atomic number 58, 64 and 71.

Give examples where the atomic mass of the elements have been corrected by Mendeleev's periodic law.

Find the position of the element having atomic number 21 in the periodic table (modern) Indicate the block in which it comes?

A compound consists of element A and B. It crystallises in a cubic crystal structure with unit cell having A atoms at the corners of the cell and B atom at the face centres of the cell. If the edge-length of the unit cell is 5Å, and the atomic masses of A and B are 60 and 90 respectively, then calculate the density of the compound.