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2.1

a. Atoms are incredibly small, and they are made out of Protons, Neutrons, and Electrons.

b. 20

2. a. Because they have the same amount of electrons.

b. Carbon-12 is nonradioactive and only has 6 nuclei, while Carbon-14 is radioactive and has 8 nuclei.

3. a. A chemical compound is a substance formed by the chemical combination of two or more elements in divine proportions.

b. Because water is a covalent bond where electrons move around in the nuclei of both atoms, and Hydrogen Peroxide is an ionic bond where one or more electrons are moved about from one atom to another.

4. a. Ionic bonds and Covalent Bonds.

b. An Ionic bond

5. I think it’s important that scientists study chemistry because it helps you understands the world around you, helps you understand the labels on products, helps you cook (scientists have to eat too), avoid dangerous chemical mixtures, and it explains how things work (like how a baking soda volcano explodes).

2.2 Assessment

pg 44

a. When the changes are unevenly distributed.

b. Water is a poler molecule.

c. Water is made out of two hydrogen molecules and one oxygen molecule. Oxygen is highly electronegative. It pulls the electrons to itself, and attracts more hydrogen molecules. These form hydrogen bonds.

2. a. Water’s polarity gives it the ability to dissolve both ionic compounds and other polar molecules.

b. The difference is the particles. Solution particles are transparent, and suspension particles are bigger and are cloudy or murky.

2.3 Assessment

1. a. The major elements of life are Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur. b. Carbon has 4 valence electrons so they can form strong covalent bonds, one carbon atom can bond with another, and it can also bind with many other elements.

2. a. Four organic compounds are protein, lipids, nucleic acid, and carbohydrates. b. protein: enzyme, catalyzes reactions; lipids: storage of energy, insulation; nucleic acid: in DNA; carbohydrates: make energy. c. Because proteins are made by small chain links that form polymers, but lipids are just one big macromolecule.

3. a. Hydrogen, Oxygen, and Carbon. b. Carbohydrate.

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