TABLE OF CONTENT S What is Chemistry 4 The Scientific Method 5 Measurement 8 Atoms and Elements 11 The Parts of an Atom 12 Elements 14 The Periodic Table 16 Elements Important to Life 19 Isotopes and Radioactive Elements 20 Molecules 24 Bonds 25 Chemical Formulas 28 Matter 29 Phases of Matter 29 Properties of Matter 31 Changes in Matter 38 Compounds Acids and Bases Mixtures and Solutions 40 Compounds 41 Acids and Bases 42 Mixtures 45 Solutions 46 Reactions 48 Chemical Reactions 48 Making and Breaking Bonds 49 Catalysts 49 Oxidation and Reduction 52 Releasing Energy 55 Explosions 56 People Who Study Chemistry 59 Types of Chemists 59 Women in Chemistry 62
What Is Chemistry Y CHEMISTRY Chemistry is the study of substances and the changes that happen to them Substances are things like food clothes and medicine Chemistry is very important Plastic bags and shoes with rubber soles would not exist without chemistry Fuels for cars airplanes and rockets would not exist without chemistry Chemical reactions or changes inside the human body are important They make it possible for people to think eat and breathe Chemistry is everywhere Chemicals in fertilizer helped these fruits and vegetables grow Without chemistry we would not have these clothes to keep us warm Enzymes in the girls stomachs will help them digest their food We know how our medicine works because of chemistry R T S I M E H C S I T A H W 4
CHEMISTRY In school it might seem we’ve solved all the mathematics problems already because most of the things What do elephant tusks and you do have right and wrong answers billiard balls have in common But mathematics is always growing As Before the invention of plastic elephant we learn new things and create new tusks were the main material used to make technologies we find new problems to billiard balls John Wesley Hyatt 1837 1920 solve invented celluloid a special kind of plastic in 1868 Celluloid proved to be the perfect ingredient for creating billiard balls as well as movie film Scientists learn about chemistry in The Scientific Method three ways They observe or watch substances They study substances and they do experiments They try to make substances change and then record what happens Scientists carefully plan how they learn about chemistry They often use a system called the scientific method to answer questions they might have The scientific method is very important It allows scientists to learn about how things work There are four parts to the scientific method 1 Scientists begin the scientific method by asking a question 2 They research information problem When gathering information scientists use observations to watch what they are studying very carefully They might write down or record their observations when collecting the information Scientists call this information data They also collect data by reading other scientists books and journal articles The Internet is another useful tool for gathering information about their question or W H A T I S C H E M I S T R Y 5
