7 14.007 Nitrogen N 5 6 10.811 Boron B 1 1.0079 Hydrogen H 20 40.08 # of protons in the atom # of Electrons in the atom # of neutrons in the atom Atomic mass of the atom Atomic # of the atom Element name Chemical symbol 7 14.007 Nitrogen N 5 6 10.811 Boron B 1 1.0079 Hydrogen H 20 40.08 Calcium Ca 30 35 65.39 Zinc Zn 13 14 27 Aluminum Al 9 10 19 Fluorine F 23 28 51 Vanadium V 17 18 Chlorine Cl 3 4 6.941 Lithium Li 79 118 196.97 Gold Au 11 12 Sodium Na 33 42 74.922 Arsenic As 50 69 118.71 Tin Sn 39.098 Potassium K

Solids, Liquids and Gases The Particle Theory Solids, Liquids and Gases

All materials exist as a Solid, Liquid or Gas All materials are made up of very very small particles held together by forces!

Solids In a Solid, the particles are held very close together so they can hardly move Solids do not flow like liquids. They generally stay in one place! Solids keep their shape. Solids always take up the same amount of space. They do not spread out like gases.

Liquids In a liquid, the particles are not so tightly packed, so they can move a little. Liquid flows easily Liquids change their shape They take the shape of the container they are in Liquids always take up the same amount of space. When liquids change shape, their volume stays the same

Gases In a gas, the particles are spread apart and can move easily Gases spread out freely Gases change their shape Gases can be squashed

Particle Theory All matter is made up of very small particles All particles in a pure substance are the same. Different substances are made of different particles There is space between particles The particles are always moving. As the particles gain energy, they move faster The particles in a substance are attracted to one another. The strength of the attractive force depends on the type of particle.

Elements, Compounds and Molecules

Elements and Compounds Some substances are made up of only 1 element. Lead (Pb), Gold (Au) Neon (Ne), Silver (Ag) Anything on the periodic table in pure form.

Of the approximately 10 million known pure substances only about 112 are elements. The rest are compounds. Salt (NaCl), Water (H2O) Sugar (C6H12O6) Caffeine

Elements and Compounds The simplest form of a substance. The smallest particle of an element is an atom. Compound: The simplest form of a material that is made up of 2 or more elements. The smallest particle of a compound is a molecule.

Which are NOT Compounds? Ice Water Gold Salt Sugar Argon Hairspray Soap Windex Steel Toothpaste Bleach Potassium Gasoline Ink Coffee People Air Shampoo Grape Juice

Compounds Elements will combine to form compounds through chemical reactions. The process involves the loss/gain of electrons, or the sharing of electrons.

Examples Atoms can gain or lose electrons to form compounds: Na + Cl  NaCl (Salt) Na loses 1 electron Cl gains 1 electron Let’s draw it! Atoms can share electrons to form compounds: H + O  H2O (Water) H and O will share electrons.

What is a Chemical Formula? The number and kind of atoms that make up a molecule of material. For example: Water's chemical formula = H2O Water consists of 2 atoms of hydrogen (H2) and one atom of oxygen (O).

How to Count Atoms E.g. 3AlCl3 The coefficient tells us how many molecules we have. Here we have three molecules of AlCl3 The subscript tells us how many of each atom we have. Each molecule has 1 Al and 3 Cl We have to multiply that by the coefficient to get the total # of atoms. 1x3 = 3 Al 3x3 = 9 Cl