1.- Calculate the molar mass of the following substances:
a)Li2CO3,
b) CS2 c)CHCl3(chloroform) ,
c)C6H8O6 (vitamin C),
d)KNO3 , f) Mg3N2
2.- The molar mass of caffeine is 194.19 g. Is the molecular formula of caffeine C4H5N2O orC8H10N4O2?3.- How many grams of sulfur (S) are needed to react completely with 246 g of mercury (Hg) to form HgS?