chemistry- word problem

Question

Determine the mass in grams of 4.12×1024 molecules of C2H4(OH)2

Answer 1

to solve this question,

1. we divide the number of molecules by Avogadro's number to get the number of moles  = 4.12 x 10²⁴ molecules ÷ 6.022 x 10²³ molecules/mole = 6.84 moles

 

2. we calculate the atomic weight of the substance by adding the atomic weights of each element two Carbons (12 each), six Hydrogen (1 each), and two Oxygen (16 each) atoms to get 62 grams/mole

 

3. finally, we multiply 62g/M x 6.84M to get ≅ 424 grams