Question

A rectangular block of lead (Pb) measures 20.0 mm X 30.0 mm X 45.0 mm. If the density of Pb is 11.34 g/cm3, calculate the mass of the block

Answer 1

1. D=M / V
Convert mm to cm then multiply to get V.
V=20.0mm * 30.0mm * 45.0mm
V=2.00cm * 3.00cm * 4.50cm=27.0cm3
11.34g/cm3=M / 27.0cm3
M= 306g

2. A cube has the same dimensions for length, height, and width, therefore volume is 1.55cm*1.55cm*1.55cm=3.724cm3
D=M / V
D=71.9g / 3.724cm3
D=19.3g/cm3

3. Volume of the sample is 41.7mL-25.5mL=16.2mL or 16.2cm3 because 1mL=1cm3
D=M / V
D=43.6g / 16.2cm3
D=2.69g/cm3

4. D=M / V
D= 3175g / 2.00m*2.00m*5.00m
Convert m to cm and multiply to get volume
D=3175g / 2.00x10^7cm3
D=1.59x10^-4g/cm3 or 0.000159g/cm3
because 1cm3=1mL
D=1.59x10^-4g/mL or 0.000159g/mL
Since I do not have the table you need to reference, I have listed the volume in scientific notation and in decimal form for you to compare to your table.

Answer 2

Taking into account the definition of density, the mass of the block of lead (Pb) is 306.18 g.

But first you must know the definition of density. Density is defined as the property that matter, whether solid, liquid or gas, has to compress into a given space. In other words, density is a quantity that shows the relationship between the weight (mass) of a substance and the volume that the same substance occupies.

Then, the expression for the calculation of density is the quotient between the mass of a body and the volume it occupies:

$density=\frac{mass}{volume}$

In this case:

• density= 11.34 $\frac{g}{cm^{3} }$
• mass= ?
• volume= 20 mm× 30 mm× 45 mm= 27000 mm³= 27 cm³ (being 1 mm³= 0.001 cm³)

Replacing in the definition of density:

$11.34\frac{g}{cm^{3} }=\frac{mass}{27 cm^{3} }$

Solving:

mass= 11.34 $\frac{g}{cm^{3} }$× 27 cm³

mass= 306.18 g

Finally, the mass of the block of lead (Pb) is 306.18 g.

Learn more about density:

• brainly.com/question/952755?referrer=searchResults
• brainly.com/question/1462554?referrer=searchResults