new in chemistry---In 3.45mg of boron there are how many of the following?
grams of boron?
moles of boron?
boron atoms?

Question

anonymous · Answer

grams of boron= are you sure its not 3.45 grams? because then it quite simply that, otherwise its 0.00345g of boron. 
moles of boron = mass/molar mass
                       = 0.00345/10.81
                       = 0.000319148 moles
boron atoms - 6.02x10^23x0.00345
                     = 2.076x10^21