What is the mass, in grams, of 9.33×1024 molecules of methanol (CH3OH)?

Answer 1

To answer this question you need to remember that:

1. 1 mole = 6.02214076 × 10²³ Avogadro's number., ( one mole of something is consist of 6.022 × 10²³ units if that substance for example 1 mole of egg/ atom/molecule= 6.022 × 10²³ eggs/atoms/molecules
2. find the molar mass of methanol CH₃OH= 12+16+4= 32 g, 1 mole of CH₃OH = 32 g.
3. Always start with what your given number., so you need to go from number of molecules to its mass in grams in final answer.

9.33 × 10²⁴ molecules of CH3OH × 1 mole ⁄6.022× 10²³ × 32 gCH₃OH ⁄ 1 mole CH₃OH= 495.78 g =496 g (3 sig. fig)