Question #b5e69

1 Answer
Sep 14, 2017

3.01 xx 10^21" molecules O"_2

Explanation:

M_(CO_2) = "220 mg"
MW_(CO_2) = "44.01 g/mol"
"O"_2 " molecules = ?"

"moles " CO_2 = (M_(CO_2))/(MW_(CO_2)) = ("220 mg"/"1000 mg/g")/"44.01 g/mol" = "0.00500 mol"

"moles O"_2 " per mole CO"_2 = 1

"Avogadro's number" = N_A = 6.022 xx 10^23" molecules/mol"

"O"_2 " molecules" = "moles CO"_2 xx "moles O"_2 /"moles CO"_2 xx N_A

= "0.00500 mol CO"_2 xx ("1 mol O"_2)/("1 mol CO"_2) xx (6.022 xx10^23 " molecules O"_2)/("1 mol O"_2)

= 3.01 xx 10^21" molecules O"_2