Like purple ribbons, blue ribbons represent many things, and among these are two types of cancer, colon cancer and colorectal cancer. Blue ribbons are also used, particularly in Canada, as a symbol for another issue that is related to cancer, anti-tobacco and anti-second-hand-smoke awareness. Light blue ribbons represent prostate cancer and, as an alternative to pink, childhood cancer. Gold is yet another alternative color for childhood cancer.
Oxygen is the most abundant element in rocks in Earth's crust, composing roughly 47 percent of the weight of all rock. The second most abundant element is silicon at 27 percent, followed by aluminum at 8 percent, iron at 5 percent, calcium at 4 percent, and sodium, potassium, and magnesium at about 2 percent each.eologists think the temperature of Earth's outer core is about 6,700 to 7,800 degrees F (3,700 to 4,300 degrees C), and the inner core may reach 12,600 degrees F (7,000 degrees C), hotter than the surface of the sun. Only the enormous pressures found at the super-hot inner core keep it solid.
Summary. Next to oxygen, silicon is the most abundant element on Earth. With four electrons in its outer shell, it readily combines with oxygen to form silicon dioxide. This compound, also known as silica, is the most common substance found in the Earth's crust and is the main ingredient in sand.Silicon is a metalloid, which means it and other metalloid elements have properties that are in between metals and non-metals, depending on what they combine with.ilicon can have properties like a metal or a non-metal depending on what other elements it combines with. Glass is a very common silicon compound that has non-metal qualities, while the silicon used in electronics can be made to act very much like a metal.