1. (a) Find the paramagnetic susceptibility of N number of hydrogen atoms at 5 K and 300 K when a magnetic field of 0.01 tesla is applied. What will be the susceptibility at these two temperatures when the field is increased to 0.1 tesla? -- 5 (b) Find the magnetic moment on the following ions Mn2+, Fe2+, Fe3+, Co2+, Ni2+, Gd3+ and Ho 3+ (the atomic numbers of Mn, Fe, Co, Ni, Gd and Ho a -25, 26, 27, 28 ,64 and 67 respectively). -- 5 (c) Find the Curie constant for one mole of Fe3+ and Gd + ions at 300 K. -- 5