Ch(3)Matter & Change John Dalton
What is Matter? Matter is anything that contains mass & volume (takes up space) Energy, such as light, heat, and sound, is NOT matter.
The Particle Theory of Matter 1. All matter is made up of very tiny objects called particles. 2. All particles have spaces between them. 3. Particles present in matter are always in motion. 4. The particles in a substance attract each other.
Elements Elements are the smallest and purest forms of particles They cannot be broken down further by ordinary means (such as simple reactions, heat, or electricity) They are only made up of one type of atom (one type of particle) Examples are Oxygen, Calcium, Iron, Carbon and Helium
Pure Substances vs. Mixtures All matter can be divided into two big categories: PURE SUBSTANCES and MIXTURES. Pure substances are made up of one type of element or compound Mixtures are a combination of pure substances (2 or more types of particles) Versus
Pure Substances Pure substances are made up of only ONE type of particle Pure substances are in the form of either elements or compounds. Atom is the smallest particle of matter that contains the characteristics of an element. Atoms consist of a nucleus with protons and neutrons in it and surrounding by electrons.
Proton is a tiny particle has a mass and positively charged. Neutron is a particle of almost the same mass of proton but electrically neutral. The number of protons in the nucleus of the atom is called atomic number. The atomic number of Carbon is 6, it has 6 protons. Atoms have the same number of protons & electrons.
The mass number is the sum of proton number and neutron number. ( nuclear number) Chemical symbols Each element has a chemical symbol and usually it is the first letter of its English or Latin name. C, O, Na
ISOTOPES Atoms with the same number of protons but different number of neutrons isotopes of an element. Radioactive isotopes; If the nuclei of some isotopes are unstable then they tend to break down emitting energy of radiation.
Why atoms bond? Chemical combination of atoms of elements are called compound. Compounds are made up of many molecules that are held together by chemical bonds. A compound is made up of only one type of particle, called a molecule Water is a molecule because it is made out of two types of atoms (oxygen and hydrogen)
Filling Energy levels
Valence Electrons are located furthest from the nucleus. They are available for bonding.
Types of Chemical bonds Ionic Bond An atom that gains or loses one or more of its valence electrons. Positive ion: atom loses an electron. Negative ion: atom gains an electron.
Ionic Bond Forms ionic compounds Ionic compounds made of ions. Transfer of e - Mostly are salts or crystals. hard solid @ 22 o C high melting point temperatures nonconductors of electricity in solid phase good conductors in liquid phase or dissolved in water.
Covalent bond Made of molecules NOT ions. Pairs of e- are shared between non-metal atoms. Properties of Covalent molecules; Low melting point (temperature) and boiling point. relatively soft solids as compared to ionic compounds nonconductors of electricity in any phase
The Four States of Matter Solid Liquid Gas Plasma
STATES OF MATTER Based upon particle arrangement Based upon energy of particles Based upon distance between particles
Kinetic Theory of Matter Matter is made up of particles which are in continual random motion.
STATES OF MATTER SOLIDS Particles of solids are tightly packed, vibrating about a fixed position. Solids have a definite shape and a definite volume. Heat
STATES OF MATTER LIQUID Particles of liquids are tightly packed, but are far enough apart to slide over one another. Liquids have an indefinite shape and a definite volume. Heat
Particles of gases are very far apart and move freely. STATES OF MATTER GAS Gases have an indefinite shape and an indefinite volume. Heat
STATES OF MATTER SOLID LIQUID GAS PLASMA Tightly packed, in a regular pattern Vibrate, but do not move from place to place Close together with no regular arrangement. Vibrate, move about, and slide past each other Well separated with no regular arrangement. Vibrate and move freely at high speeds Has no definite volume or shape and is composed of electrical charged particles
Some places where plasmas are found 1. Flames
The Sun is an example of a star in its plasma state