# How to Calculate the Specific Gravity of a Moon Rock?

## What is the process of determining the Specific Gravity of a moon rock?

A geologist finds that a moon rock whose mass is 8.98 kg has an apparent mass of 6.13 kg when submerged in water. What is the Specific Gravity (SG) of the rock?

## Calculating the Specific Gravity of a Moon Rock

The Specific Gravity (SG) of an object is the ratio of its density to the density of a reference material, which is usually water. To calculate the SG of a moon rock, you need to determine its apparent mass in water and its actual mass.

In this case, the apparent mass of the moon rock when submerged in water is 6.13 kg, while its actual mass is 8.98 kg. By using these values, you can calculate the Specific Gravity of the rock.

## Understanding the Specific Gravity Calculation

Specific Gravity (SG) is a crucial concept in geology and materials science as it helps determine the density of an object relative to water. By understanding the SG of materials like moon rocks, scientists can infer valuable information about their composition and properties.

To calculate the Specific Gravity of a moon rock, you can follow these steps:

- Measure the mass of the moon rock in air: 8.98 kg
- Submerge the moon rock in water and measure its apparent mass: 6.13 kg
- Calculate the volume of water displaced by the rock (equal to the apparent mass in water)
- Determine the density of the moon rock by dividing its mass by the volume of water displaced
- Calculate the Specific Gravity by dividing the density of the moon rock by the density of water

By following these steps, you can determine the Specific Gravity of a moon rock accurately. Understanding the SG of geological samples like moon rocks can provide valuable insights into their composition and geological history.