Question

1. a sealed 2500 cm³ flask is full to capacity with 0.36 g of a substance. determine the density of the substance. guess if the substance is a gas, a liquid, or a solid.

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unknown:

1. different kinds of wood have different densities. the density of oak wood is generally 0.7 g/cm³. if a 35 cm³ piece of wood has a mass of 25 g, is the wood likely to be oak?

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1. the density of pine is generally about 0.5 g/cm³. what is the mass of a 800 cm³ piece of pine?

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1. what is the volume of 325 g of metal with a density of 9.0 g/cm³?

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1. diamonds have a density of 3.5 g/cm³. how big is a diamond that has a mass of 0.10 g?

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1. what mass of water in grams will fill a tank 100 cm long, 50 cm wide, and 30 cm high?

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1. a graduated cylinder is filled with water to a level of 40.0 ml. when a piece of copper is lowered into the cylinder, the water level rises to 63.4 ml. find the volume of the copper sample. if the density of the copper is 8.9 g/cm³, what is its mass?

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Explanation:

Problem 3

Step1: Recall density formula

Density formula is $
ho = \frac{m}{V}$, where $
ho$ is density, $m$ is mass, $V$ is volume.

Step2: Substitute values

Given $m = 0.36\ g$, $V = 2500\ cm^3$. So $
ho=\frac{0.36\ g}{2500\ cm^3}=1.44\times 10^{-4}\ g/cm^3$. Gases have very low density (usually much less than $1\ g/cm^3$ for liquids/solids), so it's a gas.

Step1: Calculate density of wood

Using $
ho=\frac{m}{V}$, $m = 25\ g$, $V = 35\ cm^3$. So $
ho=\frac{25\ g}{35\ cm^3}\approx0.71\ g/cm^3$.

Step2: Compare with oak density

Oak density is $0.7\ g/cm^3$. The calculated density is close to $0.7\ g/cm^3$, so it's likely oak.

Step1: Recall density formula rearrangement

From $
ho=\frac{m}{V}$, we get $m=
ho V$.

Step2: Substitute values

$
ho = 0.5\ g/cm^3$, $V = 800\ cm^3$. So $m = 0.5\ g/cm^3\times800\ cm^3 = 400\ g$.

Answer:

Density is $1.44\times 10^{-4}\ g/cm^3$, substance is a gas.

Problem 4