A Natural Approach to Chemistry (2010)

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

Energy Conversions

Where does energy come from? How does energy get from one place to another? Find out how electrical current is generated and how living things get energy to move and grow. Trace the path of energy and see how energy is converted from one form to another.5 Minute Preview

Weight and Mass

Use a balance to measure mass and a spring scale to measure the weight of objects. Compare the masses and weights of objects on Earth, Mars, Jupiter, and the Moon.5 Minute Preview

Element Builder

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 numbers, the electron dot diagram, and the group and period from the periodic table are shown. Each element is classified as a metal, metalloid, or nonmetal, and its state at room temperature is also given.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

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

Conduction and Convection

Two flasks hold colored water, one yellow and the other blue. Set the starting temperature of each flask, choose a type of material to connect the flasks, and see how quickly the flasks heat up or cool down. The flasks can be connected with a hollow pipe, allowing the water in the flasks to mix, or a solid chunk that transfers heat but prevents mixing.5 Minute Preview

Heat Absorption

Shine a powerful flashlight on a variety of materials, and measure how quickly each material heats up. See how the light angle, light color, type of material, and material color affect heating. A glass cover can be added to simulate a greenhouse.5 Minute Preview

Heat Transfer by Conduction

An insulated beaker of hot water is connected to a beaker of cold water with a conducting bar, and over time the temperatures of the beakers equalize as heat is transferred through the bar. Four materials (aluminum, copper, steel, and glass) are available for the bar.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

Radiation

Use a powerful flashlight to pop a kernel of popcorn. A lens focuses light on the kernel. The temperature of the filament and the distance between the flashlight and lens can be changed. Several obstacles can be placed between the flashlight and the popcorn.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

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

Collision Theory

Observe a chemical reaction with and without a catalyst. Determine the effects of concentration, temperature, surface area, and catalysts on reaction rates. Reactant and product concentrations through time are recorded, and the speed of the simulation can be adjusted by the user.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

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

Mystery Powder Analysis

Perform multiple experiments using several common powders such as corn starch, baking powder, baking soda, salt, and gelatin. The results of the research on the known powders can then be used to analyze several unknowns using the scientific method. The unknowns can be a single powder or a combination of the known powders.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

Bohr Model: Introduction

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 energies of absorbed and emitted photons based on energy level diagrams. The light energy produced by the laser can be modulated, and a lamp can be used to view the entire absorption spectrum at once.5 Minute Preview

Electron Configuration

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 across periods and down families/groups of the periodic table.5 Minute Preview

Element Builder

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 numbers, the electron dot diagram, and the group and period from the periodic table are shown. Each element is classified as a metal, metalloid, or nonmetal, and its state at room temperature is also given.5 Minute Preview

Photoelectric Effect

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 electric field can be created to resist the electrons and measure their initial energies.5 Minute Preview

Star Spectra

Analyze the spectra of a variety of stars. Determine the elements that are represented in each spectrum, and use this information to infer the temperature and classification of the star. Look for unusual features such as redshifted stars, nebulae, and stars with large planets.5 Minute Preview

Electron Configuration

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 across periods and down families/groups of the periodic table.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

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

Colligative Properties

Determine how the physical properties of a solvent are dependent on the number of solute particles present. Measure the vapor pressure, boiling point, freezing point, and osmotic pressure of pure water and a variety of solutions. Compare the effects of four solutes (sucrose, sodium chloride, calcium chloride, and potassium chloride) on these physical properties.5 Minute Preview

Freezing Point of Salt Water

Control the temperature of a beaker of water. As the temperature drops below the freezing point, a transformation of state will occur that can be viewed on a molecular level. Salt can be added to the water to see its effect on the freezing point of water.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

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

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

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

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

Collision Theory

Observe a chemical reaction with and without a catalyst. Determine the effects of concentration, temperature, surface area, and catalysts on reaction rates. Reactant and product concentrations through time are recorded, and the speed of the simulation can be adjusted by the user.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

Boyle's Law and Charles's Law

探讨了tigate 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

Diffusion

Explore the motion of particles as they bounce around from one side of a room to the other through an adjustable gap or partition. The mass of the particles can be adjusted, as well as the temperature of the room and the initial number of particles. In a real-world context, this can be used to learn about how odors travel, fluids move through gaps, the thermodynamics of gases, and statistical probability.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

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

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

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

Rock Cycle

Play the role of a piece of rock moving through the rock cycle. Select a starting location and follow many possible paths throughout the cycle. Learn how rocks are formed, weathered, eroded, and reformed as they move from Earth's surface to locations deep within the crust.5 Minute Preview

Nuclear Decay

观察五个主要类型的核衰变: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

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

Heat Absorption

Shine a powerful flashlight on a variety of materials, and measure how quickly each material heats up. See how the light angle, light color, type of material, and material color affect heating. A glass cover can be added to simulate a greenhouse.5 Minute Preview

Radiation

Use a powerful flashlight to pop a kernel of popcorn. A lens focuses light on the kernel. The temperature of the filament and the distance between the flashlight and lens can be changed. Several obstacles can be placed between the flashlight and the popcorn.5 Minute Preview

Solar System Explorer

Survey the solar system, observing the length of a year and the orbital path of each object. The positions of the eight official planets are displayed, as well as one dwarf planet, Pluto. Learn about Kepler's Laws and how planets are classified.5 Minute Preview