Why are van der waals forces important? a) they determine how strong dipole moments will be in polar covalent molecules b) they are the strongest type of intermolecular force that can act on polar and non-polar molecules c) they are primary intermolecular attractive forces that can act between non-polar molecules d) they are the strongest type of intermolecular force that can act between atoms

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.

Calculate the ratio of h+ ions to oh– ions at a ph = 7. find the concentration of h+ ions to oh– ions listed in table b of your student guide. then divide the h+ concentration by the oh– concentration. record this calculated ratio in table a of your student guide. compare your approximated and calculated ratios of h+ ions to oh– ions at a ph = 7. are they the same? why or why not? record your comparison in table a. what is the concentration of h+ ions at a ph = 7? mol/l what is the concentration of oh– ions at a ph = 7? mol/l what is the ratio of h+ ions to oh– ions at a ph = 7? : 1

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?