What is the percent mass oxygen in acetone

27.6 %.

Explanation:

Atomic mass of C = 12.011 g/mol.

Atomic mass of H = 1.008 g/mol.

Atomic mass of O = 15.999 g/mol.

∴ The mass % of O = (Atomic mass of O / molar mass of acetone) x 100 = [(15.999 g/mol) / (58.08 g/mol)] = 27.6 %.

h let me think

answer: the figure is attached herewith.

step-by-step explanation:   we are given to sketch a unit circle and label the terminal points corresponding to

in the attached figure, we have drawn a unit circle, with centre at o(0,0) and radius 1 unit. we have labelled the points a, b, c, d and e corresponding to the angles below

∠aox = 60°,

∠box = 120°,

∠cox = 180°,

∠dox = 240°,

∠eox = 300°.

and the coordinates are a(0.5,1), b(-0.5,1), c(-1,0), d(-0.5,-1) and e(0.5,-1).

thus, the answer is complete.