A scientist is studying rocks found within layers of Earth. She finds a rock with a mass of 72 grams and a volume of 24 cm3.

Question

The table shows the average densities of rocks that are commonly found in the area where the scientist found the rock. Densities are rounded to the nearest tenth.

Average Densities of Rocks g/cm3

Shale 2.0
Quartzite 3.0
Sandstone 2.5
Marble 2.7
Limestone 1.2
According to the data, what type of rock did the scientist find?

(1 point)
Responses

Shale
Shale

Limestone
Limestone

Sandstone
Sandstone

Quartzite

Answer 1

To determine the type of rock the scientist found, we first need to calculate the density of the rock based on its mass and volume.

Density is calculated using the formula:

\[ \text{Density} = \frac{\text{Mass}}{\text{Volume}} \]

Given:

• Mass = 72 grams
• Volume = 24 cm³

Now we can calculate the density:

\[ \text{Density} = \frac{72 , \text{grams}}{24 , \text{cm}^3} = 3 , \text{g/cm}^3 \]

Now, we can compare this calculated density with the average densities of the rocks listed in the table:

• Shale: 2.0 g/cm³
• Quartzite: 3.0 g/cm³
• Sandstone: 2.5 g/cm³
• Marble: 2.7 g/cm³
• Limestone: 1.2 g/cm³

The calculated density of 3.0 g/cm³ matches the density of Quartzite.

Thus, the type of rock the scientist found is Quartzite.