Browse by Grade & Topic: Atoms

Use protons, neutrons, and electrons to build elements. As the number of protons, neutrons, and electrons changes, information such as the name and symbol of the element, the Z, N, and A...

Explore what isotopes are by adding protons and neutrons to the nucleus of an atom. Plot both stable and radioactive isotopes on a graph of neutrons vs. protons, and explore how the...

The atomic mass for each element listed in the periodic table is actually the weighted average mass of all of the different isotopes of the element. In the Average Atomic Mass Gizmo, use a...

Understand the definition of a mole and determine the Avogadro constant by adding atoms or formula units to a balance until the mass in grams is equal to the atomic or formula mass....

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Create the electron configuration of any element by filling electron orbitals. Determine the relationship between electron configuration and atomic radius. Discover trends in atomic radii...

Explore trends in atomic radius, ionization energy, and electron affinity in the periodic table. Measure atomic radius with a ruler and model ionization energy and electron affinity by...

Combine various metal and nonmetal atoms to observe how the electronegativity difference determines the polarity of chemical bonds. Place molecules into an electric field to experimentally...

Investigate the decay of a radioactive substance. The half-life and the number of radioactive atoms can be adjusted, and theoretical or random decay can be observed. Data can be interpreted...

Observe the five main types of nuclear decay: alpha decay, beta decay, gamma decay, positron emission, and electron capture. Write nuclear equations by determining the mass numbers and...

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Explore examples of nuclear fusion and fission reactions. Follow the steps of the proton-proton chain, CNO cycle, and fission of uranium-235. Write balanced nuclear equations for each step,...

Fire photons to determine the spectrum of a gas. Observe how an absorbed photon changes the orbit of an electron and how a photon is emitted from an excited electron. Calculate the...

Shoot a stream of photons through a container of hydrogen gas. Observe how photons of certain energies are absorbed, causing the electron to move to different orbits. Build the spectrum of...

Shoot a beam of light at a metal plate in a virtual lab and observe the effect on surface electrons. The type of metal as well as the wavelength and amount of light can be adjusted. An...

The Secret Service has arrested suspects accused of counterfeiting coins from 1915 valued at $50,000 each. The students act as a forensic scientist to investigate the crime scene and...