Question

Visit this PhET density simulation (http://openstaxcollege.org/l/16phetmasvolden) and select Mystery Blocks.(a) Pick one of the Mystery Blocks and determine its mass, volume, density, and its likely identity.(b) Pick a different Mystery Block and determine its mass, volume, density, and its likely identity.(c) Order the Mystery Blocks from least dense to most dense. Explain.

Short answer

(a) Mass= 18.58g, volume = 5.7cm³, density = 3.26 g/cm³. It is likely made of rubber.

(b) Mass= 8.05g, volume= 1.6cm³, density = 5.0g/cm³. It is likely made of iron.

(c) Order of the blocks from least dense to most dense:

Block (a) < Block (b)

Step-by-step solution

Definition of density

Density (ρ) is the ratio of the mass and volume of a substance.

\({\rm{\rho = }}\frac{{{\rm{mass}}}}{{{\rm{volume}}}}\)g/cm³

Determining the density of the blocks

The density of the blocks = \(\frac{m}{{\Delta V}}\), where m=mass of the block and ΔV= volume of water displaced

ΔV= (volume of the water after the block is placed in it) – (volume of water without the block)

Density of block (a) = \(\frac{{18.58g}}{{(31.2 - 25.5)ml}}\)= 3.26 g/cm³

Density of block (b) =\(\frac{{8.05g}}{{(27.1 - 25.5)ml}}\)= 5 g/cm³

Thus, we can see that block (b) is denser than block (a).