Question

How many grams of the molecule (C2H4O2) would be required to make 1 L of a 0.5 M solution of the molecule? (Carbon = 12, Oxygen = 16, Hydrogen = 1)

(A) 16
(B) 100
(C) 15
(D) 25
(E) 30

Answer 1

MC₂H₄O₂ = 2 * 12 g/mol + 4 * 1 g/mol + 2 * 16 g/mol = 60 g/mol

c = 0.5 mol/L

V = 1 L

n = c * V

n = 0.5 mol/L * 1 L = 0.5 mol

m = n * M

m = 0.5 mol * 60 g/mol = 30 g/mol

answer E

(-_-(-_-)-_-)