How many moles of

Question

How many moles of C₃H₈ contain 29.9 ×10²⁴ hydrogen atoms?

Answer 1

You first need to find the number of moles of hydrogen atoms are present. So 29.9 X 10²⁴ hydrogen atoms X 1 mole contains 6.022X 10²³ hydrogen atoms=49.6 moles H atoms. Since there are 8 moles of hydrogen atoms/mole of C₃H₈, there are 6.2 moles of C₃H₈. or you can do: 29.9 X 10²⁴ hydrogen atoms X 1 molecule C₃H₈ contains 8 atoms of hydrogen X 1 mole of C₃H₈ contains 6.022X 10²³ molecules C₃H₈.Just replace the word "contains" with a division sign and cancel like units and you arrive at 6.2 moles.