Learning About Elements: The Earth's Building Blocks
The Earth is made of matter, which exists as solid, liquid, or gas and is made up of tiny particles called atoms. Matter with only one kind of atom is an element, and the combination of elements forms compounds. Elements or compounds may be blended to form mixtures. Elements, compounds, and mixtures are the building blocks of the Earth.
In this project, you will construct pie charts showing the different elements that make up each of the three outer parts of the Earth, lithosphere, hydrosphere, and atmosphere, and the salt compounds in seawater. You will learn how elements combine to form compounds and model the attraction that holds compounds together. You will also learn about and model the changes in the phases of matter.
Purpose: To construct pie charts to represent the most abundant substances in the Earth's lithosphere.
- sheet of typing paper
- drawing compass
- protractor with 6-inch (15-cm) base
- Write the title "Elements of the Earth's Lithosphere" at the top of the paper.
- Use the compass to draw a 6-inch (15-cm) circle below the title.
- The element oxygen makes up about 47% of the elements in the Earth's lithosphere. A pie chart contains 360°. Thus, oxygen would be represented on the pie chart by an arc equal to 47% of 360°. Calculate this, rounding the answer to the nearest whole number. Example:
- Draw the 169° angle of arc on the circle by first drawing a horizontal line from the left side of the circumference to the center of the circle.
- Position the protractor on this line and mark 1690 as accurately as possible on the circumference.
- Remove the protractor and draw a line from the center of the circle to the 1690 mark. Label this area of the pie chart "Oxygen 47%."
- The element silicon makes up about 28% of the Earth's lithosphere. Calculate the angle of arc using the equation in step 3:
- Position the protractor on the line drawn in step 6 for oxygen, then mark 1010 on the circumference.
- Label this area of the pie chart "Silicon 28%."
- The rest of the lithosphere is made up of other elements. Calculate the remaining percentage by adding the known percentages together and subtracting from 100%:
- Complete the pie chart by labeling the remaining area "Other Elements 25%," as shown in Figure 9.1.
x = 47% × 360°
Note: To change a percent number to a decimal number, move the decimal to the left two places and remove the percent sign.
A pie chart is made showing percentages of the two most abundant elements in the Earth's lithosphere.
The Earth's lithosphere starts at its surface and extends to a depth of about 62.5 miles (100 km). Matter is any substance that has mass (the amount of material in a substance) and occupies space. Matter is made of atoms (smallest particles of an element that retain the properties of that element), which include electrons (negatively charged subatomic particles), protons (positively charged subatomic particles), and neutrons (neutrally charged subatomic particles). Matter made of atoms that are all alike is an element. There are 92 naturally occurring elements on Earth. Eight of these elements make up about 98% of the mass of the Earth's lithosphere. The pie chart shows that three-fourths (75%) of the Earth's lithosphere is made of just the elements oxygen and silicon. Silicon and oxygen combine with other kinds of atoms to form molecules (a combination of two or more atoms) called silicates. The attraction between atoms in a molecule that keeps them together is called a chemical bond. Matter made up of molecules that are all alike is a compound. Silicates are the most common substance in the rocky material making up the Earth's lithosphere.