What is the difference between the number of electrons in an atom of tin (Sn) and the number of electrons in an atom of oxygen (O)?

Which of these describes how heat is transferred by convection* a. sunlight travels through space without the aid of fluids or solids. b. warm air rises and takes the heat with it, eventually, it cools and sinks c. air at the equator rises and sinks at the poles. d. air molecules touch the warm ground, heating them up *not conduction

What are the trends and exceptions to the trends in electron affinity?

Beaker a contains 100 ml of 1.5 mammonia. beaker b contains 100 ml of 0.50m ammonia. how does the solution in beaker a compare to the solution in beaker b?