What is the mass of carbon in 500. g of octane?

The answer is: the mass of carbon is 420.6 grams.

m(C₈H₁₈) = 500 g; mass of octane.

M(C₈H₁₈) = 114.22 g/mol; molar mass of octane.

n(C₈H₁₈) = m(C₈H₁₈) ÷ M(C₈H₁₈).

n(C₈H₁₈) = 500 g ÷ 114.22 g/mol.

n(C₈H₁₈) = 4.38 mol; amount of octane.

In one molecule of octane, there are eight carbon atoms:

n(C) = 8 · n(C₈H₁₈).

n(C) = 8 · 4.38 mol.

n(C) = 35.02 mol; amount of carbon.

m(C) = 35.02 mol · 12.01 g/mol.

m(C) = 420.6 g; mass of carbone.

hey there!

mass = 6.75 g

volume =   9 cm³

therefore:

d = mass / volume

d   = 6.75 / 9

d = 0.7 g/cm³

answer b

weight of any object is given by

w = m*g

where m is mass of the object and g is the acceleration due to gravity.

for earth the value of g is 9.8 m/s^2 so

w=117.6 n m=12 g=?

117.6=12g => g=9.8 m/s^2

which is the force of gravity on earth.