In the table is also a list of how many grams a mole of an element weighs. The bottom line is that there are about 1. If you want to write it with all the zeros it would be:. Questions and Answers in the human body? Citation and linking information For questions about this page, please contact Steve Gagnon. The very heavy elements in you were made in exploding stars. The size of an atom is governed by the average location of its electrons. If the nucleus were the size of a peanut, the atom would be about the size of a baseball stadium.
If we lost all the dead space inside our atoms, we would each be able to fit into a particle of lead dust, and the entire human race would fit into the volume of a sugar cube. As you might guess, these spaced-out particles make up only a tiny portion of your mass. The mass of the quarks, which comes from their interaction with the Higgs field, accounts for just a few percent of the mass of a proton or neutron. Gluons, carriers of the strong nuclear force that holds these quarks together, are completely massless.
Your body is a small-scale mine of radioactive particles. You receive an annual millirem dose from the natural radioactivity originating inside of you. Your radiation dose level can go up by one or two millirem for every eight hours you spend sleeping next to your similarly radioactive loved one. You emit radiation because many of the foods you eat, the beverages you drink and even the air you breathe contain radionuclides such as Potassium and Carbon They are incorporated into your molecules and eventually decay and produce radiation in your body.
The average human produces more than positrons per day, about per hour. Metals are usually malleable , they can be bent or molded without breaking, and lustrous , or shiny. Most metals are silvery in color Fig. Most metals are solid at room temperature. One exception is mercury Hg , which is a liquid at room temperature Fig.
The elements in Group 1, including lithium Li , sodium Na, Fig. These metallic Group 1 elements have similar reactive properties. In Fig 2. Nonmetals are poor conductors of heat and electricity; they are not lustrous and exist in nature as solids, liquids, or gases. When solid, non-metals tend to be brittle, such as sulfur, which flakes apart rather than bending like a metal would Fig. The elements in Group 17, including fluorine F 2 , chlorine Cl 2 , Fig.
The nonmetals in Group 17 are all diatomic two atoms in their elemental form and have similar reactive properties.
There are other organizational features of the periodic table. Most periods have the first element of the period in Group 1 and the last element in Group An exception is the first period.
Sometimes hydrogen H is placed in Group 17, above fluorine F , because it has similar properties to the nonmetals in that group; for example, in its elemental state hydrogen exists as a diatomic gas, H2. Sometimes hydrogen is placed in both Groups 1 and Groups of elements have similar properties. The properties of some groups are so unique or important that the groups are referred to by special names.
The elements in this group are called the noble gases. Noble gases seldom react with other elements. Noble gases have many uses, for example, they are used in neon signs Fig 2. Group 1 is often referred to as the alkali metals, Group 2 as the alkaline earth metals, and Group 17 as the halogens.
The two groups that are pulled out on the bottom of the periodic table in rows are called the lanthanide rare earth series top row and the actinide series bottom row. This document may be freely reproduced and distributed for non-profit educational purposes. Skip to main content. Search form Search. Join The Community Request new password. Main menu About this Site Table of Contents. Atoms, Molecules, and Compounds. NGSS Performance Expectations: HS-PS Use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms.
The content and activity in this topic will work towards building an understanding of the structure of atoms and how elements are organized on the periodic table. Chemical Structures The properties of elements and compounds are determined by their structures. Electrostatic Forces Electrostatic forces hold atoms in molecules. Determine how charged matter interacts.
Properties of metals and nonmetals Metals Nonmetals Physical Properties Good conductor of heat and electricity Poor conductor of heat and electricity Malleable - can be beaten or deformed without cracking; pliable Brittle Ductile - can be made into wire Non-ductile Lustrous Not lustrous, may be opaque or transparent Solid at room temperature except Hg and a few other metals that are liquid at or near room temperature Solid, liquid, or gas at room temperature Chemical Properties Usually have valence electrons Usually have valence electrons Tend to lose valence electrons Tend to gain electrons.
Other Organizational Features of the Periodic Table There are other organizational features of the periodic table. Further Investigations. Table of Contents: Atoms, Molecules, and Compounds. Activity: Electrostatic Forces.
Special Features:. Representative Image:. Further Investigations: What is an Invertebrate? Question Set: What is a Mammal? Further Investigations: What is a Mammal?
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