Chemistry Help?

Question

Okay there are 2 questions. can someone help me solve these problems and explain them.

Ethylene glycol, C2H6O2, is a liquid that is the base of the antifreeze you use in your car's radiator. it has a density of 1.1335g/cm^3 at 20 degrees Celsius. If you need 500 mL. of this liguid,what mass of the compound, in grams, is required?

A sample if unknown metal is placed in a graduated cylinder containing water. The mass of the sample is 37.5g, and the water levels before and after adding the sample to the cylinder in the figure. Which metal in the following list in likely the sample(d is the density of the metal)?

A)Mg. d=1.75g/cm3
B)Fe, d+ 7.87 /cm3
C)Ag, d=10.5g/cm3
D)Al, d=2.70 g/cm3
E)Cu, d= 8.96 g/cm3
F) Pb, d= 11.3 g/cm3

Left figure the one without the metal is 7
Right Figure with the metal is 21

Answer 1

First, let's understand density. Ethylene glcol gas a density of 1.1335 grams per cm^3. A cm^3 is the same as a mL. (You will also see it written as cc - for cubic centimeter). You want 500 cm^3 (500 mL) and 1 mL weights 1.1335 grams.

In the second question you are adding 37.5 g of a metal. You know that the metal occupies 14 mL (cm^3) because the water level fifference was 14 mL (21 - 7). Therefore the density of the metal was 37.5 g per 14 cm^3 or 2.68 g/cm^3. (D) Aluminum is the most likely metal (2.70 g/cm^3).

Answer 2

1 cm^3 = 1 ml
(500 ml)(1.1335 g/ml) = 667.5 g

Assuming 1 ml graduations
ρ = (37.5 g) / (21 - 7) cm^3
ρ ≈ 2.6786 g/cm^3
ρ ≈ 2.70 g/cm^3