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Explore how chemistry discoveries have revolutionized health and materials, from antibiotics like penicillin to synthetic polymers replacing natural materials. Understand the significance of rubber, petroleum, and synthetic products. Learn about chemical reactions, helpful vs. harmful chemicals, and safety precautions.
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DO NOW • How have discoveries in chemistry impacted people’s health and lives?
Lesson 4 – Chemistry and Health (pg 386) • Alexander Fleming discovered penicillin which led the way to antibiotics. They are used to kill bacteria. • Vitamins are chemicals that are naturally found in certain foods and prevent many diseases. • Fertilizers are chemicals used by farmers to help food to grow
Silk is a very nice expensive material Made from silk worm cocoons
A french scientist made artificial silk But it easily burst into flames
Chemistry and New Materials (pg. 388) • Many materials used daily come from nature, but others were created by scientists. • Scientists worked to create a synthetic replacement for silk and eventually invented polymers. Polymers are large molecules made of identical small units connected together. • Some useful synthetic materials are plastic and cement.
The PROBLEM with Natural Rubber: • IT gets GOOEY and MELTY in hot weather! • IT gets BRITTLE and CRACKS in cold weather.
In the 1800’s: • Scientists experimented with natural rubber and added HEAT and SULFUR. • This made it more durable!
In the 1900’s • Chemists developed artificial rubber.
Petroleum is made up of: • Gasoline, • Kerosene • Diesel oil • Lubricating oil • Chemists found a way to separate gasoline molecules from the mixture petroleum!
What does SYNTHETIC mean?? • Hint : • synthesize
Natural Materials? Or synthetic? (What does synthetic mean?) • Cotton • Wool • Plastic • Nylon • Concrete • Silk
CHEMISTRY and TRANSPORTATION • Rubber for tires! • Petroleum for gasoline! • Mix of metal elements (combined in a factory or plant) and plastic (made in a lab) for car
Chemistry and New Materials • Cotton in jeans • natural • Wool in a sweater • natural • Nylon in stockings • Made in a lab • Plastic • Made in a lab • Concrete • Made in a lab!
Chemicals—Helpful vs Harmful • Chemicals are helpful when used properly!
Chemicals for Cleaning Common chemical bleaches include household chlorine bleach, a solution of approximately 3–6% sodium hypochlorite (NaClO), and oxygen bleach, which contains hydrogen peroxide or a peroxide-releasing compound such as sodium perborate • Bleach • Ammonia • Oven Cleaner
Care with Chemicals! • READ THE DIRECTIONS! • Gloves • Goggles • Open window • Do not mix without proper knowledge! • Or else: chemical reactions, lung damage, fumes, burns, explosions, death!
How Does temperature affect how long a reaction takes? – alka seltzer lab
MODELS • Model = • A useful way to understand a subject that you maybe cannot see or explore in real life • (ex: using magnets to explain what happens in a chemical reaction) • (ex: a globe to understand what the earth looks like)
Types of Chemical reactions • 1. combination • Elements or compounds come together to form new compounds • A + B AB • 2. decomposition • Compounds split apart to form smaller compounds or elements • AB A + B • 3. replacement • Compounds split apart and parts switch places • AB + CD AD + BC