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  • Holt Textbooks
  • Holt Science & Technology: Blue (2006)

Holt Science & Technology: Blue (2006)

3: Properties and States of Matter

Screenshot of Density Laboratory

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


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Screenshot of Mystery Powder Analysis

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


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Screenshot of Phase Changes

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


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Screenshot of Temperature and Particle Motion

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


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4: Atoms

Screenshot of Element Builder

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


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6: Chemical Bonding

Screenshot of Covalent Bonds

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


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Screenshot of Ionic Bonds

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


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9: Forces and Motion

Screenshot of Distance-Time Graphs

Distance-Time Graphs

Create a graph of a runner's position versus time and watch the runner complete a 40-yard dash based on the graph you made. Notice the connection between the slope of the line and the speed of the runner. What will the runner do if the slope of the line is zero? What if the slope is negative? Add a second runner (a second graph) and connect real-world meaning to the intersection of two graphs. 5 Minute Preview


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Screenshot of Distance-Time and Velocity-Time Graphs

Distance-Time and Velocity-Time Graphs

Create a graph of a runner's position versus time and watch the runner run a 40-yard dash based on the graph you made. Notice the connection between the slope of the line and the velocity of the runner. Add a second runner (a second graph) and connect real-world meaning to the intersection of two graphs. Also experiment with a graph of velocity versus time for the runners, and also distance traveled versus time. 5 Minute Preview


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Screenshot of Fan Cart Physics

Fan Cart Physics

Gain an understanding of Newton's Laws by experimenting with a cart (on which up to three fans are placed) on a linear track. The cart has a mass, as does each fan. The fans exert a constant force when switched on, and the direction of the fans can be altered as the position, velocity, and acceleration of the cart are measured. 5 Minute Preview


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Screenshot of Free-Fall Laboratory

Free-Fall Laboratory

Investigate the motion of an object as it falls to the ground. A variety of objects can be compared, and their motion can be observed in a vacuum, in normal air, and in denser air. The position, velocity, and acceleration are measured over time, and the forces on the object can be displayed. Using the manual settings, the mass, radius, height, and initial velocity of the object can be adjusted, as can the air density and wind. 5 Minute Preview


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Screenshot of Feed the Monkey (Projectile Motion)

Feed the Monkey (Projectile Motion)

Fire a banana cannon at a monkey in a tree. The monkey drops from the tree at the moment the banana is fired from the cannon. Determine where to aim the cannon so the monkey catches the banana. The position of the cannon, launch angle and initial velocity of the banana can be varied. Students can observe the velocity vectors and the paths of the monkey and banana. 5 Minute Preview


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10: The Energy of Waves

Screenshot of Basic Prism

Basic Prism

Shine white light or a single-color beam through a prism. Explore how a prism refracts light and investigate the factors that affect the amount of refraction. The index of refraction of the prism, width of the prism, prism angle, light angle, and light wavelength can be adjusted. 5 Minute Preview


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Screenshot of Herschel Experiment

Herschel Experiment

Shine sunlight through a prism and use a thermometer to measure the temperature in different regions of the spectrum. The thermometer can be dragged through the visible spectrum and beyond. This recreates the experiment of William Herschel that led to the discovery of infrared radiation in 1800. 5 Minute Preview


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Screenshot of Laser Reflection

Laser Reflection

Point a laser at a mirror and compare the angle of the incoming beam to the angle of reflection. A protractor can be used to measure the angles of incidence and reflection, and the angle of the mirror can be adjusted. A beam splitter can be used to split the beam. Both plane and irregular mirrors can be used. 5 Minute Preview


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Screenshot of Longitudinal Waves

Longitudinal Waves

Observe the propagation of longitudinal (compression) waves in a closed or open tube with evenly-spaced dividers. The strength and frequency of the waves can be manipulated, or waves can be observed as individual pulses. Compare the movement of dividers to graphs of displacement, velocity, acceleration and pressure. 5 Minute Preview


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Screenshot of Refraction

Refraction

Determine the angle of refraction for a light beam moving from one medium to another. The angle of incidence and each index of refraction can be varied. Using the tools provided, the angle of refraction can be measured, and the wavelength and frequency of the waves in each substance can be compared as well. 5 Minute Preview


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Screenshot of Sound Beats and Sine Waves

Sound Beats and Sine Waves

Listen to and see interference patterns produced by sound waves with similar frequencies. Test your ability to distinguish and match sounds as musicians do when they tune their instruments. Calculate the number of "sound beats" you will hear based on the frequency of each sound. [Note: Headphones are recommended for this Gizmo.] 5 Minute Preview


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11: Heat and Heat Technology

Screenshot of Energy Conversion in a System

Energy Conversion in a System

A falling cylinder is attached to a rotating propeller that stirs and heats the water in a beaker. The mass and height of the cylinder, as well as the quantity and initial temperature of water can be adjusted. The temperature of the water is measured as energy is converted from one form to another. 5 Minute Preview


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Screenshot of Heat Transfer by Conduction

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


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Screenshot of Temperature and Particle Motion

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


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12: Magnetism and Electricity

Screenshot of Advanced Circuits

Advanced Circuits

Build compound circuits with series and parallel elements. Calculate voltages, resistance, and current across each component using Ohm's law and the equivalent resistance equation. Check your answers using a voltmeter, ammeter, and ohmmeter. Learn the function of fuses as a safety device. 5 Minute Preview


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Screenshot of Circuits

Circuits

Build electrical circuits using batteries, light bulbs, resistors, fuses, wires, and a switch. An ammeter, a voltmeter and an ohmmeter are available for measuring current, voltage and resistance throughout the circuit. The voltage of the battery and the precision of the meters can be adjusted. Multiple circuits can be built for comparison. 5 Minute Preview


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Screenshot of Magnetic Induction

Magnetic Induction

Measure the strength and direction of the magnetic field at different locations in a laboratory. Compare the strength of the induced magnetic field to Earth's magnetic field. The direction and magnitude of the inducting current can be adjusted. 5 Minute Preview


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13: Atomic Energy

Screenshot of Half-life

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


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Screenshot of Nuclear Decay

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


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14: Earth's Systems and Cycles

Screenshot of Cell Energy Cycle

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


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Screenshot of Rock Cycle

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


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Screenshot of Water Cycle

Water Cycle

Control the path of a drop of water as it travels through the water cycle. Many alternatives are presented at each stage. Determine how the water moves from one location to another, and learn how water resources are distributed in these locations. 5 Minute Preview


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15: Environmental Problems and Solutions

Screenshot of Water Pollution

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


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16: Stars, Galaxies, and the Universe

Screenshot of Solar System Explorer

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


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Screenshot of Star Spectra

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


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17: A Family of Planets

Screenshot of Solar System Explorer

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


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19: Heredity

Screenshot of Human Karyotyping

Human Karyotyping

Sort and pair the images of human chromosomes obtained in a scan. Find differences in the scans of the various patients to find out specific things that can cause disease, as well as determining the sex of the person. 5 Minute Preview


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Screenshot of Mouse Genetics (One Trait)

Mouse Genetics (One Trait)

Breed "pure" mice with known genotypes that exhibit specific fur colors, and learn how traits are passed on via dominant and recessive genes. Mice can be stored in cages for future breeding, and the statistics of fur color are reported every time a pair of mice breed. Punnett squares can be used to predict results. 5 Minute Preview


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Screenshot of Mouse Genetics (Two Traits)

Mouse Genetics (Two Traits)

Breed "pure" mice with known genotypes that exhibit specific fur and eye colors, and learn how traits are passed on via dominant and recessive genes. Mice can be stored in cages for future breeding, and the statistics of fur and eye color are reported every time a pair of mice breed. Punnett squares can be used to predict results. 5 Minute Preview


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20: Genes and DNA

Screenshot of Building DNA

Building DNA

Construct a DNA molecule, examine its double-helix structure, and then go through the DNA replication process. Learn how each component fits into a DNA molecule, and see how a unique, self-replicating code can be created. 5 Minute Preview


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Screenshot of DNA Analysis

DNA Analysis

Scan the DNA of frogs to produce DNA sequences. Use the DNA sequences to identify possible identical twins and to determine which sections of DNA code for skin color, eye color, and the presence or absence of spots. 5 Minute Preview


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Screenshot of RNA and Protein Synthesis

RNA and Protein Synthesis

Go through the process of synthesizing proteins through RNA transcription and translation. Learn about the many steps involved in protein synthesis including: unzipping of DNA, formation of mRNA, attaching of mRNA to the ribosome, and linking of amino acids to form a protein. 5 Minute Preview


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21: Population Changes

Screenshot of Evolution: Mutation and Selection

Evolution: Mutation and Selection

Observe evolution in a fictional population of bugs. Set the background to any color, and see natural selection taking place. Inheritance of color occurs according to Mendel's laws and probability. Mutations occur at random, and probability of capture by predators is determined by the insect's camouflage. 5 Minute Preview


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Screenshot of Evolution: Natural and Artificial Selection

Evolution: Natural and Artificial Selection

Observe evolution in a fictional population of bugs. Set the background to any color, and see natural selection taking place. Compare the processes of natural and artificial selection. Manipulate the mutation rate, and determine how mutation rate affects adaptation and evolution. 5 Minute Preview


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Screenshot of Microevolution

Microevolution

Observe the effect of predators on a population of parrots with three possible genotypes. The initial percentages and fitness levels of each genotype can be set. Determine how initial fitness levels affect genotype and allele frequencies through several generations. Compare scenarios in which a dominant allele is deleterious, a recessive allele is deleterious, and the heterozygous individual is fittest. 5 Minute Preview


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Screenshot of Natural Selection

Natural Selection

You are a bird hunting moths (both dark and light) that live on trees. As you capture the moths most easily visible against the tree surface, the moth populations change, illustrating the effects of natural selection. 5 Minute Preview


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22: The Fossil Record

Screenshot of Human Evolution - Skull Analysis

Human Evolution - Skull Analysis

Compare the skulls of a variety of significant human ancestors, or hominids. Use available tools to measure lengths, areas, and angles of important features. Each skull can be viewed from the front, side, or from below. Additional information regarding the age, location, and discoverer of each skull can be displayed. 5 Minute Preview


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