Density Calculations in Science 8
In Science 8, one of the key concepts that students learn about is density. Density is a measure of how much mass is contained in a given volume of a substance. It is an important property of matter that helps us identify and compare different materials. In this worksheet, students will practice calculating the density of various substances and solving related problems.
What is Density?
Density is a measure of how tightly packed the molecules in a substance are. It is calculated by dividing the mass of an object by its volume. The formula for density is:
Density = Mass ÷ Volume
Units of density are typically expressed in grams per cubic centimeter (g/cm3) or kilograms per cubic meter (kg/m3). For example, the density of water is 1 g/cm3.
Calculating Density
To calculate the density of a substance, you need to know its mass and volume. Mass is typically measured in grams (g) or kilograms (kg), and volume is measured in cubic centimeters (cm3) or cubic meters (m3). Once you have these measurements, you can plug them into the formula for density and solve for the answer.
Sample Problem
Let’s work through a sample problem to demonstrate how to calculate density. Suppose you have a block of wood with a mass of 50 grams and a volume of 25 cm3. To find the density of the wood, you would divide the mass by the volume:
Density = 50 g ÷ 25 cm3 = 2 g/cm3
So, the density of the wood is 2 g/cm3.
Practice Problems
Now it’s time for you to try some practice problems on your own. Here are a few questions for you to solve:
- A sample of metal has a mass of 100 grams and a volume of 10 cm3. What is the density of the metal?
- A liquid has a mass of 500 grams and a volume of 250 cm3. What is the density of the liquid?
- A block of ice has a volume of 1,000 cm3 and a density of 0.9 g/cm3. What is the mass of the ice?
Answers to Practice Problems
Here are the answers to the practice problems:
- The density of the metal is 10 g/cm3.
- The density of the liquid is 2 g/cm3.
- The mass of the ice is 900 grams.
Conclusion
Understanding density is an important skill in Science 8. By mastering the concept of density and learning how to calculate it, students can better understand the properties of different materials and how they interact with each other. Practice makes perfect, so keep practicing your density calculations to improve your skills!