How many neutrons does 85rb have?

Rb has two isotopes - one having 48 neutrons and the other having 50 neutrons. The atomic mass number of an isotope is the sum of the protons plus neutrons in the nucleus, so the two stable isotopes of Rb are designated 85Rb and 87Rb (their atomic mass numbers).

HOPE THIS HELPED X

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.