1. The atomic number of Tin (chemical symbol Sn) is 50. Thus is has 50 protons and 50 electrons. The mass-118 isotope has 118 - 50 = 68 neutrons.

2. Calcium (chemical symbol Ca) has 20 electrons and 20 protons. The Ca II ionization state corresponds to a Ca ion of charge + 1. Thus, this ion has 20 - 1 = 19 electrons and 20 protons. We cannot specify the number of neutrons without futher information, since there are different isotopes of Ca.