Ancient Skies Gods and Monsters

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Earn 50 dollars with new SoFi account and an interest rate of 2.25 percent annually

SoFi is an online bank account that offers 2.25 percent interest per year. That is a lot more than you would get with a regular checking or savings account at many banks. SoFi also offers investment options you can use to invest and grow your money by diversifying your investment between stocks and bonds. I recommend using SoFi over opening a regular saving or checking account because it doesn't have a fee and you can also learn some tips on how to save and manage your money. 

Use this link to get a 50 dollars bonus when you sign up and deposit at least 100 dollars into your SoFi account. 

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10 Rules for a Rich Life

1. A rich life means you can spend extravagantly on the things you love as long as you cut costs mercilessly on the thing you don't

2. Focus on the Big Wins-the five to ten things that get you disproportionate results, including automating your saving and investing, finding a job you love, and negotiating your salary. Get the Big Wins right and you can order as many lattes as you want.

3. Investing should be very boring-and profitable-over the long term. I get more excited eating tacos than checking my investment returns.

4. There's a limit to how much you can cut, but no limit to how much you can earn. I have readers who earn $50,00/year and ones who earn $750,000/year. They both buy the same loaves of bread. Controlling spending is important, but your earnings become super-linear.

5. Your friends and family will have lots of "tips" once you begin your financial journey. Listen politely, then stick to the program.

6. Build a collection of "spending frameworks" to use when deciding on buying something. Most people default to restrictive rules ("I need to cut back on eating out..."), but you can flip it and decide what you will always spend on. If you are thinking about buying a book just buy it. Don't waste even five second debating it. Applying even one new idea from a book is worth it.

7. Beware of the endless search for "advanced" tips. So many people seek out high-level answers to avoid the real, hard work of improving step by step. It's easier to dream about winning the Boston Marathon than to go out for a ten-minute job every morning. Sometime the most advanced thing you can do is the basics, consistently.

8. You're in control. This is not a Disney movie and nobody's coming to rescue you. Fortunately, you can take control of your finances and build your rich life.

9. Part of creating your rich live is the willingness to be unapologetically different. Once money is not a primary constraint, you will have the freedom to design your own rich life, which will almost certainly be different from the average person's. Embrace it. This is the fun part!

10 Live life outside the spreadsheet. Once you automate your money, you will see that the most important part of a rich life is outside the spreadsheet-it involves relationships, new experiences, and giving back.

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High School AP Chemistry

Introduction And Philosophy

Basic Concepts Of Quantitative Reasoning

Quantitative Reasoning In Everyday Life

Quantitative Reasoning In Chemistry—density

The Si (Metric) System Of Measurement

Converting Between Systems Of Measurement

Elements, Atoms, And The Periodic Table

Ions, Compounds, And Interpreting Formulas

Isotopes And Families Of Elements

The Mole

Solving Mole Problems

Avogadro's Hypothesis And Molar Volume

Percent Composition And Empirical Formulas

Solving Empirical Formula Problems

Writing And Balancing Chemical Equations

An Introduction To Stoichiometry

Stoichiometry Problems

Advanced Stoichiometry

An Introduction To Molarity

Solving Molarity Problems

Advanced Molarity Problems

Basic Concepts Of Chemical Equilibrium

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Free Science Magazine Subscription

The Scientist is a website that offer free information about Biology and life science. They offer free magazine to subscriber. You can sign up to receive two type of magazine, the digital which is sent directly to your email or you can sign up to get the printed copy sent to your address. I used to website to learn new things about Biology. 

Click Here to visit their website.

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Finviz - Free Stock Screener

With this stock screener you can screen stock using a wide variety of fundamental, technical, and descriptive metrics. The screener will also provide charts, quotes, and other useful information once you've drilled down and come up with results that are worth further exploration. I use this to search for high paid dividend stocks and how well a company is doing before I invest.

Click Here to use Finviz

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What is the difference between debt and equity funding

A bank these days can lend up to 80% of the total cost of the project (land + permits + construction + sales). This means in order to make a project possible a developer only needs to come up with 20% of the money required themselves, with the rest being borrowed.

A good project needs to deliver at least a 20% profit on the total money invested in the project. However, out of the total money invested only 20% is equity and the rest is being borrowed. Let's say we have a 12-month project which cost $100 and generated a profit of $20. Out of the $100 investment, only $20 was equity by the developer and the rest $80 was lent by the bank at 5%. 

So out of the $20 profit, $4 goes to the bank as interest on its $80 at 5%. And the remaining $16 goes to the developer for his $20 investment. This is an 80% return on equity in one year. Not bad at all! If the project was two years long then the yearly equity return would be 40%. For a 4 year project, this would be 20%. The annual return on equity is also called Internal Rate of Return or IRR.

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Understanding Basic Electronics

DC Voltage

AC Voltage

Semiconductors

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Understanding Modern Electronics

Electricity and Electronics

Circuits and Symbols

Instruments and Measurement

AC versus DC

Up The Treble Down the Bass

Semiconductors - The Miracle Material

Transistors and How They Work

Transistors As Amplifiers

Building An Audio Amplifier

The Ideal Amplifier

Feedback Magic

Electronic Feedback

Amplifier Circuits Using Op-Amps

More Fun With Op-Amps

Using Op-Amps With Circuits

Digital Versus Analog

Electronics Goes Digital

Flip-Flop Circuits

Shift and Divide Your USB and Your Watch

Digital Memory

Digital Counters

Digital To Analog

Analog To Digital

Your Future In Electronics

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Biology - Science of Life

1. The Scope of Life

2. More on the Origin of Life

3. The Organism and the Cell

4. Proteins-How Things Get Done in the Cell

5. Which Molecule Holds the Code

6. The Double Helix

7. The Nuts and Bolts of Replicating DNA

8. The Central Dogma

9. The Genetic Code

10. From DNA to RNA

11. From RNA to Protein

12. When Mistakes Happen

13. Dividing DNA Between Dividing Cells

14. Mendel and His Pea Plants

15. How Sex Leads to Variation

16. Genes and Chromosomes

17. Charles Darwin and The Origin of Species

18. Natural Selection in Action

19. Reconciling Darwin and Mendel

20. Mechanisms of Evolutionary Change

21. What Are Species and How Do New Ones Arise

22. More on the Origin of New Species

23. Reconstructing Evolution

24. The History of Life, Revisited

25. From Cells to Organisms

26. Control of Gene Expression 1

27. Control of Gene Expression 2

28. Getting Proteins to the Right Place

29. Genetic Engineering and Biotechnology

30. How Cells Talk-Signals and Receptors

31. How Cells Talk-Ways That Cell Respond

32. From One Cell to Many in an Organism

33. Patterns of Early Development

34. Determination of Differentiation

35. Induction and Pattern Formation

36. Genes and Development

37. Homeostasis

38. Hormones in Animals

39. What is Special about Neurons

40. Action Potentials and Synapses

41. Synaptic Integration and Memory

42. Sensory Function

43. How Muscles Work

44. The innate Immune System

45. The Acquired Immune System

46. Form and Function in Plants 1

47. Form and Function in Plants 2

48. Behavior as an Adaptive Trait

49. Energy and Resources in Living Systems

50. How Energy is Harnessed by Cells

51. Enzymes-Making Chemistry Work in Cells

52. Cellular Currencies of Energy

53. Making ATP-Glycolysis

54. Making ATP-Cellular Respiration

55. Making ATP-The Chemiosmotic Theory

56. Capturing Energy from Sunlight

57. The Reactions of Photosynthesis

58. Resources and Life Histories

59. The Structure of Populations

60. Population Growth

61. What Limits Population Growth

62. Costs and Benefits of Behavior

63. Altruism and Mate Selection

64. Ecological Interactions Among Species

65. Predators and Competitors

66. Competition and the Ecological Niche

67. Energy in Ecosystems

68. Nutrients in Ecosystems

69. How Predictable Are Ecological Communities

70. Biogeography

71. Human Population Growth

72. The Human Asteroid

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How Tax Works

Taxation is the main way in which governments raise revenue needed to pay for public spending. Governments may tax the public directly (for instance, through income tax) or indirectly (via VAT for example). 

How it works

Governments have the unique privilege of being able to demand that anyone in their country pay taxes. These can be divided into "direct" taxes, which are paid from earnings, either by people or institutions, and "indirect" taxes, which are paid for out of consumer spending. Taxes can be levied as a share of spending or income, or as a flat rate. A progressive tax system is one in which richer individuals pay proportionately more tax. Questions surrounding the level of taxation are hotly debated. As a result levels of taxation, and laws about who or what pays for which taxes, vary significantly from country to country.

Taxes and behavior

Some taxes are designed to reduce the amount of revenue that goods earn. Because a newly-levied or increased tax on a product puts up its price, that item becomes less attractive to buy. Where a product is harmful, higher taxes such as on cigarettes can be a way to reduce public consumption. In cases where consumer behavior does not alter much in response to higher pricing, however, the extra tax is likely to raise much more money. This can make some taxes very appealing for governments looking for revenues. 

Direct and indirect taxes

People have to pay taxes on either their income, or on what they spend. Some typical taxes on an individual in the US are shown below.

Need to know

> Tax return: A document used by individuals and businesses to record income.

> Tax rate: The amount at which an individual or a company is taxed; rates vary according to a person's income or a company's returns.

> International agreements: Contracts that act as a restraint on taxation, such as in stopping import duties from being levied.

Tax evasion and avoidance

Because tax systems vary so widely from country to country, it is possible to exploit the differences in international tax rates in order to reduce the total amount of tax due. This is termed tax "evasion" when it is done illegally, and tax "avoidance" when performed legally, although in practice the boundaries between the two are blurred. Some jurisdictions deliberately set very low tax rates to attract investment; some also provide secrecy around the identity of those investing there. This has led to accusations that such areas are acting as "tax havens." This means that, instead of providing a legitimate location for economic activity, they are allowing major corporations and the very wealthy to avoid paying taxes they should be paying.

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Governments and money

A country's government and central bank play a key role in the circulation of money in the economy. They monitor money supply, send funding to key sectors of society, and ensure that cash flows back to them for state spending.

How it works

A healthy economy requires a good money supply. Although it is difficult to control the supply of money directly, government monetary policy can help to influence it. The most important institution in monetary policy is the central bank, which is critical in determining interest rates and can be used to inject more money into the economy via open market operations or through quantitative easing. Governments may also control the flow of money via taxes and other capital controls, and by restricting borrowing and lending. However, these mechanisms are imperfect in the modern monetary system, since commercial banks are largely free to decide the terms of their lending. Attempts to directly control money supply tend to fail.

Money supply and a healthy economy

As a healthy body depends on a good blood supply to receive nutrients, so a healthy economy requires a good money supply to keep the cycle of spending going: as one person spends, another earns, then spends, and so on. If this cycle slows, the economy may begin to decline. The government, via the central bank-which is like the beating heart of the economy-helps to keep money flowing. Meanwhile, the government also ensures that funding reaches key areas of society, while collecting revenues for state spending. Economic policies around interest rates, reserve ratios, open market operations, and quantitative easing are all focused on maintaining money supply. A body may have optimal blood supply, but it is down to the cells to effectively utilize the nutrients. In the same way, while a government can improve money supply, economic growth then depends on how effectively individuals and businesses are able to convert this money into useful goods and services to raise living standards.

Need to Know

> Money supply: The total amount of money circulating in a country, from currency to less liquid forms.

> Central bank: An institution that provides financial services to the government and commercial banks, implements monetary policies, sets interest rates, and controls money supply.

> Currency in circulation: Money that is physically used to conduct transactions between customers and businesses.

The case for independent central bank

Many central banks were made independent of the government in the early 2000s, although they are still required to be both transparent and accountable. The 2008 crash led some to question whether independent banks are desirable.

Pros	Cons
> Monetary policy can be more impartial as banks have no interest in maintaining electoral popularity. > As they are unaffected by the electoral cycle they can plan and implement long-term policies. > Independent banks have tended to maintain lower rates of inflation.	> Unelected bank cannot be voted out, arguably making  them less accountable. > Central bank controls may not be enough to avert financial crises without government aid. > Governments may blame banks for recessions, so eroding trust.

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Understanding Shares

Shares are units of ownership interest in a corporation that are available for investors to buy or sell. Companies create shares in order to raise capital, which they can invest to grow their business.

How It Works

Shareholders are investors who buy the shares a company creates, and who therefore own a part of the company. When shareholders buy a share, it is usually an "ordinary share" or "common share," which means that they can vote in the election of the company's executive team approve or vote against new share issues and other money raising activities, and in some cases receive payouts known as dividends. Shareholders are entered on the company's shareholder register, which is a list of all the investors who hold a stake in it. Investors buy shares for capital growth (holding to underlying value or price of the shares will rise, and for income if the shares pay dividends. Share price rise and fall based on a company's financial performance, general economic news, and market sentiment-how investors feel about a company or the wider economy. If a share price fluctuates in a short space time it is said to be volatile. If one company's share price is volatile it can indicate investor worries about that company; if volatility affects all share prices it can indicate instability in entire markets.

Need To Know

> Listed A share that appears on the register (list) of the stock exchange on which it is being traded (bought or sold).

> Quote The most recent price at which a share has been traded. Stock exchanges are now all electronic, and prices can be seen changing minute by minute during the course of the day.

> Stocks "Stocks" describes the ownership of shares in general. "Shares" refers to the ownership of shares in a particular company.

Issuing Shares

Companies issues shares when they need money to invest or pay off costs. When an investor buys a share, they become a shareholder and own a small part of the company.

Understanding Shares

1. Once shares have been issued they can then be traded on the stock market.

2. The price of a share favored by investors tend to rise; if investors lose confidence, the price tends to fall.

3. If a company does well, shareholders share in the returns. This is what makes buying share so exciting to investors.

4. Shareholders buy part of a company. If share values fall, there is no guarantee that they will get their money back.

5. If a company goes bust, shareholders will probably lose most or all of their initial capital.

6. If a company fails, shareholders lose their investment but they are not responsible for a company's debts.

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Understanding Bonds

Companies and governments sell bonds to raise money without issuing shares. They are effectively fixed-term loans bought by investors who receive interest until the end of that term.

How It Works

Bonds are securities for long-term debt, although they are not always held until the end of their term. The price of a bond rises and falls depending on current interest rates, and on how likely investors feel the bond issuer is to repay the initial sum invested. There are different kinds of bonds such as savings bonds company bonds, and government bonds (also known as US Treasury securities), and some can be traded between investors. In savings bonds, investors deposit a lump sum with a retail savings institution (such as a bank), receive regular interest, and are repaid the original sum in full. In other types of bond, repayment of the original sum is not guaranteed, since the issuer could go bust. Because the risk of government default is so small, gilts are seen as the least risky bond type.

Investing In Bonds

When choosing a bond, investors must balance the total sum received in interest against the likelihood of the capital sum (initial cash investment) actually being repaid at the end of the term. They must also decide whether a bond offers good value by analyzing its current yield. This compares the interest paid by the bond with its current value on the secondhand market. Although bondholders have a slightly higher chance of being paid than shareholders if a company collapses, there is no guarantee of payment.

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Finance for Non-Financial Managers

1. Welcome

2. What you should know before watching this course

3. The purpose of finance

4. Entrepreneurs, investors, and facilitators

5. What is accounting

6. Overview of the financial statement

7. Balance sheets

8. Income statements

9. Statement of cash flows

10. What is financial ratio analysis

11. Return on equity

12. The DuPont framework

13. The DuPont framework - Ford and General Motors

14. What is the next step in the analysis

15. The operating cycle

16. Cash management

17. Managing receivables and inventory

18. Considering all of your costs (fixed, variable, and the contribution margin)

19. How to calculate your break-even point

20. Drafting a budget

21. Review of the budgeting steps

22. Understanding income taxes

23. Tax brackets

24. Tax deductions and tax credits

25. Next steps

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Fundrise

Fundrise is a REIT or Real Estate Investment Trust that allows you to invest into real estate by buying Fundrise stocks and earn a certain percent as dividend return on your investment. Fundrise is a good long term investment for those that wants to invest into real estate. The current rate of return is about 8-10 percent annually and if you have 10,000 dollars or more, you can upgrade your account to advanced investment which have a higher rate of return. You can watch the video below to learn more about Fundrise.

Follow this link to start investing into Fundrise.

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Worthybond Investment

Worthybond is a website that allows you to buy bonds for 10 dollars each and you can earn a 5% interest rate of return annually. The great thing about Worthybond is you can sell your bonds back at anytime and withdraw your money. I recommend investing in this because the percent you earn is much higher than putting your money in the bank and only put some in your bank so you can use it when you need it and only withdraw from Worthybond when your cash is low in your bank account. Click here to sign up an account with Worthybond and start investing.

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Nuclear Physics

1. A Tour of the Nucleus and Nuclear Forces

2. The curve of Binding Energy Fission and Fusion

3. Alpha, Beta and Gamma Decay

4. Radiation Sources, Natural and Unnatural

5. How Dangerous Is Radiation

6. The Liquid Drop Model of the Nucleus

7. The Quantum Nucleus and Magic Number

8. Particle Accelerators Schools of Scattering

9. Detecting Subatomic Particles

10. How to Experiment with Nuclear Collisions

11. Scattering Nucleons in Singles or in Pairs

12. Sea Quarks, Gluons, and the Origin of Mass

13. Nuclear Fusion in Our Sun

14. Making Elements Big Bang to Neutron Stars

15. Splitting the Nucleus

16. Nuclear Weapons Were Never ôAtomicö Bombs

17. Harnessing Nuclear Chain Reactions

18. Nuclear Accidents and Lessons Learned

19. The Nuclear Fuel Cycle and Advanced Reactors

20. Nuclear Fusion Obstacles and Achievements

21. Killing Cancer with Isotopes, X-Rays, Protons

22. Medical Imaging CT, PET, SPECT, and MRI

23. Isotopes as Clocks and Fingerprints

24. Viewing the World with Radiation

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Basic Math

1. Adding 1 and 2 digit number

2. Adding 3 and 4 digit number

3. Subtracting 1 and 2 digit number

4. Subtracting 3 and 4 digit number

5. Introduction to multiplication

6. Multiply by 1s

7. Multiply by 2s

8. Multiply by 3s

9. Multiply by 4s

10. Multiply by 5s

11. Multiply by 6s

12. Multiply by 7s

13. Multiply by 8s

14. Multiply by 9s

15. Multiply by 10s

16. Multiply by 11s

17. Multiply by 12s

18. Multiplication Problems

19. Division with no remainder

20. Division with a remainder

21. Dividing 2, 3, and 4 digit numbers with remainder

22. Simplifying Fractions

23. Adding and Subtracting Fractions

24. Adding and Subtracting Fractions and Finding the Common Denominator

25. Multiplying Fractions

26. Dividing Fractions

27. Decimal Place Value

28. Adding, Subtracting, and Multiplying Decimals

29. Dividing Decimals

30. Percents

31. Ratio and Proportion

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Algebra Word Problems

1. Number Problems

2. Digit Problems

3. Problems Involving Averages

4. Coin and Money Problems

5. Age Problems

6. Problems Involving Speed, Distance and Time

7. Mixture Problems

8. Interest Problems

9. Lever Problems

10. Work Problems

11. Problems Involving Quadratic Equations 

12. Problem Involving Geometry

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Algebra Two

1. Graphing Equations

2. The Slope of a Line

3. Writing Equations of Lines

4. Graphing Inequalities

5. Solving Systems of Equations by Graphing

6. Solving Systems of Equations by Substitution

7. Solving Systems of Equations by Addition

8. Solving Systems of Equations in Three Variables

9. Simplifying Radical Expressions

10. Adding and Subtracting Radical Expressions

11. Multiplying and Dividing Radical Expressions

12. Solving Equation Containing Radicals

13. Fractional Exponents

14. Solving Polynomial Equations

15. The Quadratic Formula

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Cosmology - The History and Nature of Our Universe

1. The Journey Ahead

2. Denizens of the Universe

3. Overall Cosmic Properties

4. The Stuff of the Universe

5. The Sweep of Cosmic History

6. Measuring Distances

7. Expansion and Age

8. Distances Appearances, and Horizons

9. Dark Matter and Dark Energy

10. Cosmic Geometry: Triangles in the Sky

11. Cosmic Expansion: Keeping Track of Energy

12. Cosmic Acceleration: Falling Outward

13. The Cosmic Microwave Background

14. Conditions during the First Million Years

15. Primordial Sound: Big Bang Acoustics

16. Using Sound as Cosmic Diagnostic

17. Primordial Roughness: Seeding Structure

18. The Dark Age: From Sound to the First Stars

19. Infant Galaxies

20. From Child to Maturity: Galaxy Evolution

21. Giant Black Holes - Construction and Carnage

22. The Galaxy Web - A Relic of Primordial Sound

23. Atom Factories - Stellar Interiors

24. Understanding Element Abundances

25. Light Elements Made in the Big Bang

26. Putting It Together: The Concordance Model

27. Physics at Ultrahigh Temperatures

28. Back to a Microsecond: The Particle Cascade

29. Back to the GUT: Matter and Forces Emerge

30. Puzzling Problems Remain

31. Inflation Provides the Solution

32. The Quantum Origin of All Structure

33. Inflation's Stunning Creativity

34. Fine Tuning and Anthropic Arguments

35. What's Next for Cosmology?

36. A Comprehensible Universe?

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Thermodynamics

Thermometers and Temperature Scales

Expansion and Contraction of Solids and Liquid

Kinetic Theory of Gases

Heat

Latent Heat and Phase Change

Heat Transfer

Work, Heat, and PV Diagrams

First Law of Thermodynamics

Heat Engines and the Second Law of Thermodynamics

Refrigerators

Entropy

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Physics 3 Electricity and Magnetism

The Capacitor

Capacitor Problems

Capacitors in Circuits, Part 1

Capacitors in Circuits, Part 2

Energy Storage in a Capacitor

Capacitors with a Dielectric Part 1

Capacitors with a Dielectric Part 2

Electric Current and Current Density Part 1

Electric Current and Current Density Part 2

The Magnetic Field

Magnetic Force on a Charged Particle Part 1

Magnetic Force on a Charged Particle Part 2

Equations of an Orbiting Charge in a Magnetic Field

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Introduction to Power Electronics - Switch Realization

This video lecture talks about the realization of switches in power converters using semiconductor devices such as power transistors and diodes.

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Organic Chemistry making plastic experiment

Carbon is the most remarkable of all elements. Its unique atomic structure enables it to link atoms together in long chains or rings in countless ways - so many that there is a whole field of chemistry, called "organic" chemistry, devoted to studying compounds of carbon. Every living organism, from lichens to people, is made from carbon compounds. Many carbon compounds are made with hydrogen only, but there are millions of them. These "hydrocarbons" include all the world's fossil fuels - coal, oil gasoline, gas - fuels formed from the carbon of dead vegetation around 300 million years ago. Other carbon chemicals, such as alcohols and sugars, include oxygen. The largest and most complicated carbon molecules of all are "polymers," from which plastics and many other man-made materials are made.

Making Plastic Experiment

Most plastics are man-made from oil and natural gas. But you can make your own very simple plastic from casein, the curds in mild, and set it in a mold to make your own plastic ornament.

Things you will need:

Muslin, Jars, Milk, Vinegar, Spoon, Saucepan, Rubberband, and Heater.

1. Warm 10 FL oz (0.3 liters) of milk in a pan, but do not boil. Add a tablespoon of vinegar and stir in.

2. A white, rubbery material, the casein, forms in the milk. Strain it off through muslin held over a container.

3. Squeeze the milk through the muslin until you have recovered all of the solid rubbery casein.

4. Push the casein into a suitable mold, such as a cookies cutter, or shape it by hand. Then leave it to set. 

Over a few days, the casein will gradually dry out and harden as the protein molecules bond tightly together. You can speed the process by leaving it on a warm radiator. If you wish to make a brooch, push a safety pin into the back while it is still soft. Once it has set paint it in your own design.

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Rock and Dissolved

Can something as soft as rain dissolve something as strong as a rock? You can find out in this science experiment. 

Things you will need:

Three cup drinking glasses
Lemon juice
Vinegar
Water
3 pieces of chalk

1. Pour 1/2 glass lemon juice into glass 1. Pour 1/2 glass vinegar into glass 2, and pour 1/2 glass water into glass three

2. Put 1 piece of chalk into each of the glasses. Make sure part of the chalk is in the liquid.

3. Place the glasses where they won't be knocked over.

4. Check on the glasses over the next few days. What is happening?

The chalk dissolves in the vinegar and in the lemon juice. When humans release carbon dioxide in the air, it dissolves into raindrops and makes rain become naturally acidic. Over time, rainfall which can dissolve and erode rocks. The chalk you used in the experiment is made of the rock limestone or calcium carbonate. When acids react with limestone, they eat away at the rock and start to break it apart. Lemon juice and vinegar are acids. They are much stronger than acid rain, so erosion happens more quickly. You can see how acid rain can affect rocks over hundreds and thousands of years.

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Melting point experiment

Rock is solid, water is liquid, and air is gas - but they do not have to be. Every substance in the world is a solid, liquid, or a gas, yet, given the right conditions, each can change into any of these "states of matter": solid, liquid, or gas. Even rock melts to liquid lava in the heat of a volcano; water freezes solid on very cold nights. It all has to do with the tiny particles - atoms and molecule - that make up every substance. In a slid, the particles are tightly knit together, like the bricks in a wall. So solids are fairly rigid and tend to keep their shape. You can pick up many solids but not water. When the solid gets hot, however, the bonds between the particles begin to break up and solid the melts to a liquid.

Besides heat, pressure can also melt solid, as this simple experiment shows. Hang a weighted wire over an ice cube. The wire cuts slowly through the cube as the pressure melt the ice.

Melting Point Experiment

Measure the melting point of different substances - the temperature at which a solid turns to a liquid. (Adult supervision is advised)

Things you will need:

Heater

Thermometer

Test tube

Heatproof jug or pan

Test solid (butter, chocolate, Jello, wax, etc)

How to do it:

Hold a test tube containing a small quantity of the test solid. Heat the water slowly in the jug or pan. Keep shaking the tube gently. As soon as the solid begins to melt remove the tube from the water and check the temperature. Repeat the experiment twice for each solid. Beware the test tube can get quite hot. If you can, hold it with a cloth or barbecue tongs.

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The bouncing egg experiment

Things you will need:

Eggs

Water

Vinegar

Flashlight

A bowl

1. Put 1 whole raw egg in a glass of water

2. Put 1 whole raw egg in a glass of vinegar

3. The eggs are the same, aren't they? Now, leave them for a few hours.

4. Look at both eggs. Do they still look the same? The egg in the water is the same, but the egg in the vinegar has changed. The shell has begun to fizz. The acid in the vinegar dissolves the calcium carbonate that is in the shell.

5. Look carefully. Does the egg in vinegar still have its shell? Touch it. It no feels and looks like a rubber ball, doesn't it?

6. Leave both eggs alone for 7 days. After that time, take the egg in the vinegar to a dark room and shine a flashlight at it. What do you see? The light bounces off the egg, doesn't it?

7. Take the egg out of the glass of vinegar. Hold the egg a little bit over a bowl.

8. Let the egg drop. Do you think it will splatter? Try it.

What happens:

Your egg bounces! Try it again getting a little higher each time. See how high you can make the egg bounce. What do you think will happen if you try to bounce the egg that was in the water? Hold it over the bowl and try.

Why:

• A chemical change takes place in the egg when left in vinegar.
• The vinegar, which is an acid, reacts with the calcium carbonate of the eggshell.
• The change makes the shell go soft, then disappear. This is called "decalcification".
• The egg in the glass of water does not chemically change.

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