Caffeine is a stimulant drug found in many beverages such as coffee, tea, and soft drinks. In one molecule of caffeine, there are:
Twice as many nitrogen atoms as oxygen atoms
Twice as many carbon atoms as nitrogen atoms
Two more hydrogen atoms than carbon atoms
Which of the following is the chemical formula for caffeine?
A. C2H4NO
B. C4H6 Ni2O
C. Ca10H8N4O6
D. C8H10N4O2

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year