Question

Quartz is one of the most common minerals in Earth's crust. Its specific gravity is 2.65. A 5-gallon bucket of water weighs 40 pounds. How much would a 5 -gallon bucket of quartz weigh?

Short answer

A 5-gallon bucket of quartz would weigh 106 pounds.

Step-by-step solution

Understand Specific Gravity

Specific gravity is a dimensionless number that describes the density of a mineral compared to the density of water. Quartz has a specific gravity of 2.65, meaning it is 2.65 times denser than water.

Determine the Weight of Water

A 5-gallon bucket of water weighs 40 pounds. This is the baseline weight for water of the same volume.

Calculate the Weight of Quartz

Since quartz's specific gravity is 2.65, a 5-gallon bucket of quartz will weigh 2.65 times the weight of an equivalent volume of water. Thus, the weight of a 5-gallon bucket of quartz is calculated as: Weight of quartz = Specific Gravity × Weight of water = 2.65 × 40 pounds.

Perform the Multiplication

Calculate 2.65 × 40 to find the weight of the 5-gallon bucket of quartz. This multiplication gives a result of 106 pounds.

Key concepts

Quartz Density

The concept of quartz density revolves around how compact the substance is. Quartz, a prevalent mineral found in the Earth's crust, has a specific gravity of 2.65. This means that quartz is 2.65 times as dense as water.
Specific gravity is a way to express density without using units, as it's merely a ratio. Since water's density is about 1 gram per cubic centimeter, quartz's density would be 2.65 grams per cubic centimeter. Remember, the higher the specific gravity, the denser the material.
This dense composition is important when calculating how much a certain volume will weigh, especially when compared to substances like water. Understanding the specific gravity helps in estimating how heavy large chunks would be, like in buckets or larger geological samples.

Mineral Density Comparison

Mineral density comparison involves looking at different minerals to see which are heavier for the same volume. This is crucial for geologists and engineers when assessing what minerals will be efficient for construction or when mining.
Quartz is often used as a benchmark for other minerals because it is a ubiquitous component on Earth. Other minerals might have lower specific gravity, like talc, which is softer and less dense than quartz. Alternatively, minerals like galena have much higher specific gravity.

• Quartz with a specific gravity of 2.65 acts as the standard reference,
• while metals such as gold (specific gravity ~19.3) are significantly denser.

Comparing their specific gravities offers insights into their physical properties and potential applications.

Weight Calculation of Minerals

Weight calculation of minerals, such as quartz, relies on both its specific gravity and the reference weight of the equivalent volume of water. This process is essential in fields like geology, mining, and materials science.
Let's revisit our example of a 5-gallon bucket. Knowing that the weight of a 5-gallon bucket filled with water is 40 pounds, we can calculate the weight of a bucket filled with quartz using its specific gravity. We multiply the specific gravity by the water's weight to get the equivalent weight in quartz:
\[\text{Weight of Quartz} = \text{Specific Gravity} \times \text{Weight of Water} \]For quartz, this equation is:
\[\text{Weight of Quartz} = 2.65 \times 40 = 106 \text{ pounds}\]Understanding this relationship allows us to accurately predict how much different minerals will weigh, which is crucial for transportation, construction, and economic assessment of mined materials.