Chemistry in the Community (2006)

Water Pollution

Get to know the four main types of pollution present in the environment, and then look at a variety of real-world examples as you try to guess what type of pollution is represented by each situation. All of the real-world situations can be viewed every day in different parts of the world. 5 Minute Preview

Density Laboratory

With a scale to measure mass, a graduated cylinder to measure volume, and a large beaker of liquid to observe flotation, the relationship between mass, volume, density, and flotation can be investigated. The density of the liquid in the beaker can be adjusted, and a variety of objects can be studied during the investigation. 5 Minute Preview

Ionic Bonds

Simulate ionic bonds between a variety of metals and nonmetals. Select a metal and a nonmetal atom, and transfer electrons from one to the other. Observe the effect of gaining and losing electrons on charge, and rearrange the atoms to represent the molecular structure. Additional metal and nonmetal atoms can be added to the screen, and the resulting chemical formula can be displayed. 5 Minute Preview

Phase Changes

Explore the relationship between molecular motion, temperature, and phase changes. Compare the molecular structure of solids, liquids, and gases. Graph temperature changes as ice is melted and water is boiled. Find the effect of altitude on phase changes. The starting temperature, ice volume, altitude, and rate of heating or cooling can be adjusted. 5 Minute Preview

Solubility and Temperature

Add varying amounts of a chemical to a beaker of water to create a solution, observe that the chemical dissolves in the water at first, and then measure the concentration of the solution at the saturation point. Either potassium nitrate or sodium chloride can be added to the water, and the temperature of the water can be adjusted. 5 Minute Preview

Balancing Chemical Equations

Balance and classify five types of chemical reactions: synthesis, decomposition, single replacement, double replacement, and combustion. While balancing the reactions, the number of atoms on each side is presented as visual, histogram, and numerical data. 5 Minute Preview

Chemical Equations

Practice balancing chemical equations by changing the coefficients of reactants and products. As the equation is manipulated, the amount of each element is shown as individual atoms, histograms, or numerically. Molar masses of reactants and products can also be calculated and balanced to demonstrate conservation of mass. 5 Minute Preview

Stoichiometry

Solve problems in chemistry using dimensional analysis. Select appropriate tiles so that units in the question are converted into units of the answer. Tiles can be flipped, and answers can be calculated once the appropriate unit conversions have been applied. 5 Minute Preview

Covalent Bonds

Choose a substance, and then move electrons between atoms to form covalent bonds and build molecules. Observe the orbits of shared electrons in single, double, and triple covalent bonds. Compare the completed molecules to the corresponding Lewis diagrams. 5 Minute Preview

Dehydration Synthesis

Build a glucose molecule, atom-by-atom, to learn about chemical bonds and the structure of glucose. Explore the processes of dehydration synthesis and hydrolysis in carbohydrate molecules. 5 Minute Preview

Boyle's Law and Charles's Law

Investigate the properties of an ideal gas by performing experiments in which the temperature is held constant (Boyle's Law), and others in which the pressure remains fixed (Charles's Law). The pressure is controlled through the placement of masses on the lid of the container, and temperature is controlled with an adjustable heat source. Gay-Lussac's law relating pressure to temperature can also be explored by keeping the volume constant. 5 Minute Preview

Temperature and Particle Motion

Observe the movement of particles of an ideal gas at a variety of temperatures. A histogram showing the Maxwell-Boltzmann velocity distribution is shown, and the most probable velocity, mean velocity, and root mean square velocity can be calculated. Molecules of different gases can be compared. 5 Minute Preview

Greenhouse Effect

Within this simulated region of land, daytime's rising temperature and the falling temperature at night can be measured, along with heat flow in and out of the system. The level of greenhouse gases present in the atmosphere at any given time can be adjusted, allowing the long-term effects to be investigated. 5 Minute Preview

Cell Energy Cycle

Explore the processes of photosynthesis and respiration that occur within plant and animal cells. The cyclical nature of the two processes can be constructed visually, and the simplified photosynthesis and respiration formulae can be balanced. 5 Minute Preview

pH Analysis

Test the acidity of common substances using pH paper. Materials including soap, lemon juice, milk, and oven cleaner can be tested by comparing the color of pH strips to a standard scale. 5 Minute Preview

pH Analysis: Quad Color Indicator

Test the acidity of many common everyday substances using pH paper (four color indicators). Materials including soap, lemon juice, milk, and oven cleaner can be tested by comparing the color of the pH strips to the calibrated scale. 5 Minute Preview

Bohr Model of Hydrogen

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 hydrogen based on photons that are absorbed and emitted. 5 Minute Preview

Nuclear Decay

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 atomic numbers of daughter products and emitted particles. 5 Minute Preview

Half-life

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 visually using a dynamic graph, a bar chart, and a table. Determine the half-lives of two sample isotopes as well as samples with randomly generated half-lives. 5 Minute Preview

Limiting Reactants

Explore the concepts of limiting reactants, excess reactants, and theoretical yield in a chemical reaction. Select one of two different reactions, choose the number of molecules of each reactant, and then observe the products created and the reactants left over. 5 Minute Preview