Chemistry is said to be an interesting subject. Of course, many of us are grappling to memorize the periodic table: the atomic number and mass, yet for some they deem it as practice.
I love Chemistry that is why when I was in high school I was a member of the Science Club. Maybe, I was just too curios and interested in all of God's creations and gifts to man.
Chemistry Exercises for SMA UN Exam - Natural Science Program
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Atoms are the building blocks of chemistry. They are the smallest component of anything; molecules.
Chemists study the behavior and characteristics of substances. These are called the properties of a substance. All substances are made ups of tiny particles called atoms. A substance the size of a pinhead contains billions of atoms.
An atom is the smallest unit of a substance that can exist and retain the properties of that substance. Each element has its own chemical name and a shortened name known as a chemical symbol.
Most symbols are abbreviations of the chemical name, like h for hydrogen. However, some symbols come from other languages. For example, the chemical symbol for gold, Au, comes from its Latin name, aurum.
The states of matter define how things move and how we can differentiate one substance from another.
Substances are divided into solid, liquids or gases. These are known as the states of matter. It is known as a change of state. It normally occurs because of a change in the energy of a substance as a result of heating or cooling.
Many substances can exist in more than one state. In a chemical reaction, it is important to know in which state the various chemicals are being used. This is done by placing the symbol (s) for solid, (l) for liquid, and (g) for gas after the name of the substances.
Evidence of molecules
The molecules in liquids and gases are continually moving in a completely random way. This can be seen when smoke molecules are viewed under a microscope. This movement is known as "Brownian motion."
The gradual missing of two or more different gases or liquids is called diffusion. This mixing is caused by molecules of different substances colliding and intermingling. This is why you can smell perfumes (whose molecules diffuse through the air) from some distance away.
So to answer the kid's question: Is water liquid or solid? Many substances can exist in more than one state. It is liquid when it flows freely and solid in the form of ice - until the change again.
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