Could someone help me out with this question?

Question

A chemist wishes to determine the density of an unknown purple liquid. She constructs a cylindrical aluminum container, whose inside radius measures 0.500 inches, with a height of 4.800 inches. When empty, this cylinder has a mass of 91.257 g. When filled with purple liquid its mass was 252.900 g. What is the density of this liquid, in terms of g/cm3?

Answer 1

Woah.

Ok first lets convert the inches into cm. 1 inch = .0254 m; so then .5 in =.0127m and 1.27cm; and 4.8 in = 12.192 cm.

Now density is mass/volume. So lets find the volume of the cylinder using v=3.14(r^2)h; so 3.14(1.27)^2(12.192) = 61.778 cm^3.

Now the mass of the liguid = 252.9g - 91.257 g = 161.643 g

So the density = 161.643g/61.778 ml which is the same as 2.6165 g/cm3 or 2.62 rounded to 3 sig figs.

Cheers

Answer 2

hints...

density is mass / volume

volume of the liquid = internal volume of the cylinder

mass of the liquid = (mass of liquid + cylinder) - mass of cylinder

watch the units...

solution...

volume of a cylinder = area of bottom x height = π r² x h

= 3.1415 x (0.500 in)² x 4.800 in = 3.77 in³

mass of liquid  = 252.900 g - 91.257 g = 161.643 g

density = 161.643 g / 3.77 in³ = 42.9 g / in³

= 42.9 g / in³ x (1in / 2.54 cm)³ = 2.62 g/cm³