Two elements X and Y have atomic number 15 and a respectively. The ratio of wavelength of `K_alpha` X-rays emitted by both is 1:4. Find the value of a

Two elements X and Y have atomic numbers 10 and 14 respectively. Identify the group numbers of these elements in the periodic table.

Two elements X and Y have the same atomic mass but this atomic number are 20 and 21 respectively X and Y are

Atomic numbers of two element are 31 and 41. Find the ratio of the wavelength of the K_(alpha) are

The two elements have their atomic numbers as Z_1 and Z_2 The ratio of the wavelength lambda_1 and lambda_2 corresponding to their K_alpha lines is

Two elements X and Y are isotonic having atomic weight 54 and 56 respectively. If the atomic number of X is 26, then the atomic number of Y will be

The half lives of radioactive elements X and Y are 3 mintue and 27 minute respectively. If the activities of both are same, then calculate the ratio of number of atoms of X and Y.