In distillation, separation is achieved by difference in---​

Joan writes four numbers on the board in standard form, and then she writes their scientific notation

Write the chemical formula for a compound that is made of an element from group 1 and an element from group 17

As we move from left to right across the periodic table, what is the general trend? a) atomic radii increase. b) electronegavitiy decreases. c) nuclear shielding increases. d) metallic character decreases.