AIM : What makes up matter? Do Now:

AIM : What makes up matter? Do Now: Substances: table salt, sugar, water, aluminum foil and copper wire. Look at the different substances listed above and write down which substances you think are elements and which are compounds.

Chemistry of Life Why it matters: All living things are made of matter, so understanding the structure and behavior of matter can help us understand how our body works

An atom is the smallest unit of matter that cannot be broken down by chemical means. Atoms are made of three types of particles: 1.Protons - positively charged 2.Electrons- negatively charged 3.Neutrons- have no charge Protons and Neutrons make up the nucleus of the atom. Electrons move around the nucleus . https://www.youtube.com/watch?v=o-3I1JGW-Ck

The structure labeled A - ______ The structure labeled B - _______ The structures labeled C & D – _______________ _______________

An Element is a substance made up of atoms that have the same number of protons (same kind of atoms).Elements cannot be broken down into simpler substances by chemical means. Examples of elements you must know : Hydrogen (H), Carbon (C) ,Oxygen(O), Nitrogen(N) , Phosphorus (P) Sulfur (S), Sodium (Na), Chlorine (Cl).

Chemical Bonds The electron cloud of an atom has levels. Electrons in the outermost level are called valence electrons. Atoms are stable when their valence shell ( the outermost level) contains 8 electrons . Atoms combine with other atoms to complete their valence shell with 8 electrons. Chemical bonds form between these atoms which become part of the compound. A compound is a substance made of two or more different elements joined together by chemical bonds.

You need to know : The difference between an element and a compound. For example : Na – is an element ( consists of the same kind of atoms , sodium atoms) NaCl - is a compound ( consists of two different elements sodium and chlorine) Identify the following as an element or a compound : Oxygen Carbon dioxide Water Iron

1. The smallest unit of matter that cannot be broken down by chemical means is a(n) a. element. b. atom. c. molecule. d. electron. 2. Which of the following particles is found in an atom’s nucleus? a. electron b. electron cloud c. isotope d. proton

Aim: Why do atoms bond? Do Now: Identify the differences between : Atom / Molecule Element/ compound

Types of bonds : Covalent Bonds – form between atoms that share their valence electrons A group of atoms joined together by covalent bonds is called a molecule. Molecules make up compounds. atoms molecules

https://www.youtube.com/watch?v=IOXxFaHbIXg

Ionic Bonds When an atom gains or loses electrons it results in a positive or negative charge. Remember: when electrons are lost – more protons left = positively charge atom. when electrons are gained – more electrons= negatively charged atom. An atom with an electric charge is called an ion. Oppositely charged ions are attracted to each other and are held together by ionic bonds.

Ionic compounds: Name this compound Which of these elements have lost electrons and which has gained? Can you tell how many electrons lost and how many gained? Rust

Solubility The partially charged ends of water molecules are attracted to other polar molecules (sugar) or ions(salt). That makes them soluble in water. Nonpolar substances (oil, fat, grease) are insoluble in water. Hydrogen Bonds – forces that hold together molecules consisting of hydrogen and other atoms. Hydrogen bonds play important role in many of the molecules that make up living things. Example : water molecules are held together by hydrogen bonds, so are the two strands of DNA.

Compare and contrast three types of bonds. Make a T-chart Distinguish between an element and a compound.

AIM: What makes water a unique substance? Do now : Why are water molecules called polar molecules?

Unique Properties of water : Ice floats - most of the substances are more dense in a solid form than a liquid form, but water is different. Ice is less dense than liquid water. Water absorbs and retains heat. This helps organisms maintain homeostasis.

3. Cohesion – water molecules stick to each other. Drops have ball shape. 4. Adhesion – water molecules stick to other surfaces made from polar molecules

Assessment: • Which of the following examples illustrates cohesion? • A. Water molecules adhere to the polar molecules of another substance. • B. Water freezes and ice floats on water • C. Water takes a longer time to heat and cool • compared to the air above it. • D. Water droplets on a surface of a car pulled together into a ball shape.

Discuss with your partner and write down your answer: Cells contain mostly water. If cells contained mostly oil, how would an organism’s ability to maintain homeostasis be affected? Try to be specific.

Acids and Bases • Acids • form extra hydronium ions when dissolved in water (H+ ) • Sour ( no tasting!) • pH <7 • Corrosive to metal and skin • Bases • Form extra hydroxide ions when dissolved in water (OH- ) • Bitter (no tasting!) • Slippery (soapy) • pH >7

Scientists use something called the pH scale to measure how acidic or basic a liquid is. The scale measures values from 0 all the way up to 14. Distilled water is 7 (right in the middle). Acids are found between 0 and 7. Bases are from 7 to 14. There are also very strong acids with pH values below 1, such as battery acid. Bases with pH value near 14 include drain cleaner. These chemicals are very dangerous. https://www.brainpop.com/science/matterandchemistry/acidsandbases/

AIM : What makes up matter? Do Now: