Question

What is the total number of atoms in the molecule C3H8?

A.8

B. 3

6.11

D. 2

Answer 1

The answer is C because C=3 and H=8 and it makes up 11.

Answer 2

Chemical Formula of propane C3H8, mole mass (C)12*3+(H)1*8=44 g (1 mole)

44 g also corresponds molar volume 22,4 l

36 g from 44 g is 81% of 1 mole

Avogadro Constant is N = (6,0230 + 0,0002) 1023x ~602000000000000000000000 the quantity of molecules in 1 mole

Quantity of molecules in 36 g (6,0230 + 0,0002) 1023x * 0,81

~487620000000000000000000

Quantity of atoms 487620000000000000000000 * 11 (why eleven? because every molecule of propane consists of 11 atoms 3 -carbon and 8-hydrogen = 3+8 =11)

So, ~5 363 820 000 000 000 000 000 000 is quantity of atoms in 36 g of propane.