democritus (~2500ya)democritus (~2500ya) 2 subatomic particles 2-1 the nature of matter atomic facts...

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Atoms2-1 The Nature of Matter

What do we call the smallest unit of matter?Who named it?What does it mean in Greek?How many atoms would make a row 1cm long?What does this indicate?Atoms are made up of particles collectively referred to as what?List the 3 types.

Democritus (~2500ya)

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Subatomic Particles

Atomic Facts2-1 The Nature of Matter

What characteristic do protons and neutrons have in common?How are they different?What charge do electrons carry and how do they compare in mass to protons & neutrons?Where is each type of subatomic particle found in an atom?What keeps the electrons in the atom?What keeps the electrons away from the nucleus?In a typical atom, how do the number of each type of subatomic particle compare?What does this mean for the overall charge of a typical atom?

What do we call an atom with a different number of protons?

What do we call an atom with a different number of neutrons?

What do we call an atom with a different number of electrons?

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Elements and Isotopes2-1 The Nature of Matter

What did ancient alchemists identify as elements?How is an element defined today?How are elements represented and organized?

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Where do most elements come from?What is an element's atomic number?What trend in atomic number can you identify in the periodic table?How many elements are known?How many are commonly found in living organisms?

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What is an element's mass number (atomic mass)?What are isotopes?Why are most atomic masses reported on the periodic table decimals (not whole numbers)?Explain why/how this atom is especially important for life as we know it and the study of biology.

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How are isotopes identified (what measurable characteristic is different)?What are the isotopes of carbon?Do isotopes have the same number of electrons?Do isotopes have the same chemical properties (bond with other atoms the same)?What makes some isotopes radioactive?What are 4 ways radioactive isotopes are scientifically useful?

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Chemical Compounds2-1 The Nature of Matter

What is a compound, in terms of elements, proportions & properties?Is oxygen a compound? Why or why not?How do scientists symbolize the composition of compounds?Write the chemical formulas for the following: Carbon Dioxide, Water, Hydrochloric Acid, Sulfuric Acid, Sodium Chloride, Hydrogen Peroxide, Glucose.

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Chlorine atom (Cl)Sodium atom (Na)

Chloride ion (Cl-)Sodium ion (Na+)

Ionic Bonds2-1 The Nature of Matter

How many electrons are found in a neutral sodium atom?How many in chlorine?What are these “rings” and distances known as?What is the maximum number of electrons that the inner-most ring appears to be able to hold? Second ring? Third?Only the electrons in the outer—most ring are able to participate in a chemical bond. What are these electrons called?When the neutral sodium atom loses an electron, what will be its overall charge?When the neutral chlorine atom gains an electron, what will be its overall charge?What is an atom called when it becomes charged in this way?How will the sodium and chlorine interact once they gain their overall charge?What kind of bond is this? What is the relative strength of this bond type?What kind of compound is this? What is the name of this compound?What is the chemical formula? Is this a molecule?

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Covalent Bonds2-1 The Nature of Matter

How many valence electrons are in a neutral oxygen atom BEFORE binding with hydrogen?How many electrons would fill oxygen's valence energy level?How many valence electrons are in a neutral hydrogen atom BEFORE binding with oxygen?How many electrons would fill hydrogen's valence energy level?Refer to the figure, how can oxygen fill it's valence energy level?How can hydrogen fill it's valence energy level?How many electrons is each atom sharing with another atom?What kind of bond is this?How does it compare in strength to an ionic bond?Write the chemical formula for this compound.What kind of compound is it?What is this type of bond called if it involves sharing four or six electrons, respectively?

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Van der Waals Forces2-1 The Nature of Matter

What are Van der Waals Forces? (What are they between and why?)How do they compare in strength to ionic and covalent bonds?How is this Tokay Gecko able to cling to smooth surfaces, like glass, and walk upside down on the ceiling?

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2-2 Properties of Water

Label + and – regions ofthe model above.

Polarity

As for most molecules, the + and – charges in a water molecule are equal so that overall the molecule is _____?However, note that the molecule is not linear. How would you describe the molecule in terms of shape and the positions of the types of atoms, or elements?Considering the number of positively charged protons in the nuclei of each atom, which would you predict has a greater affinity (attraction) for electrons?Therefore, which end of the water molecule would you predict to have a more negative charge?Which positive?This uneven distribution of charge across the water molecule means that water molecules are _____?

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2-2 Properties of Water Hydrogen Bonding

Label + and – regions and the hydrogenbonds of the model above.

The polarity of water molecules produces many unique emergent properties (magical even!). Using “+” and “-” symbols, label each atom in the diagram with its polar charge.As you know, opposite charges ____?What do the dotted lines in the diagram represent?Each water molecule is capable of interacting with how many other water molecules in this way?Compare and contrast this type of bonding with ionic bonding, covalent bonding and Van der Waals forces, in terms of strength and what is being bound.

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2-2 Properties of Water Cohesion

More magical properties due to the polarity of water! Explain how polarity and hydrogen bonding makes water cohesive.Explain how cohesion produces water's surface tension that can support a “microecosystem” known as the surface film.

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2-2 Properties of Water Adhesion

Due to polarity, water molecules are not only able to hydrogen bond with each other, but other molecules too! What is this property called?Use this knowledge to explain why the air-water interface (meniscus), shown in this photo, is “u” shaped, instead of straight across.

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2-2 Properties of Water Capillarity

The very small glass tube in the top photo is known as a capillary tube. The red substance inside it is blood (label them).What is the primary component of blood?What do plants need to move up from the soil through their stems to the leaves?Water will move against gravity through or into very fine tubes or mesh. What is this property called?What two other properties of water produce this property?

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Na+

Na+

Cl -Cl -

WaterWater

Solutions and Suspensions2-2 Properties of Water

Define a mixture.One type of mixture is a solution. Define solution using the terms solute and solvent.Is water a good solvent?Why?What types of compounds does water dissolve best (are soluble)?In the diagram, observe how the water molecules are interacting with the dissolved sodium and chloride ions. Explain why this happens.Life is in aqueous solution!!!

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Solutions and Suspensions2-2 Properties of Water

What is the other type of mixture?Define it.Explain how blood is both a solution and a suspension.

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Acids, Bases, and pH2-2 Properties of Water

Look at the top figure. Water molecules can dissociate. What does this mean?Note that when a hydrogen dissociates it leaves behind its electron. What is the resulting charge on the hydrogen?What is this ion called (label it)?What is its chemical formula or symbol?The remaining oxygen and hydrogen are left with an extra electron. What is the resulting charge?What is this ion called (label it)?What is its chemical formula or symbol?The bottom figure will be explained in class. Label as much as you can.

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Acids, Bases, and pH

The pH Scale

Human blood

Milk

Sea water

Normal rainfall

Pure water

2-2 Properties of Water

What does the pH scale measure?What is the range of the pH scale?Pure water and certain solutions have pH=7. What is this known as?How do the concentrations of hydrogen and hydroxide ions compare at pH=7?Solutions with pH >7 are _____?Solutions with pH<7 are _____?

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Acid rainTomato juice

Lemon juice

Stomach acids

The pH Scale


How do the concentrations of hydrogen and hydroxide ions compare at pH<7?What does a lower pH value represent?

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The pH Scale

Soap

Bleach

Oven cleaner

Ammonia solution


How do the concentrations of hydrogen and hydroxide ions compare at pH>7?What does a higher pH value represent?

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Any substance that when dissolved in water increases the hydroxide ion concentration is known as a ______?Any substance that when dissolved in water increases the hydrogen ion concentration is known as an _____?

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Most living things exist in what pH range?What is the pH of human blood?Your body must keep the pH of your blood the same. What is this concept of “staying the same” called?One way your body accomplishes this is through buffers. Define buffer in this context.

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275 pm

Liquid

Ice

2-2 Properties of Water The Density Anomaly

Observe the figure. Which has the greater distance between water molecules, liquid water, or ice?Based on this, which has a greater density?Use this knowledge to explain why ice floats.

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2–3 Carbon Compounds Organic Compounds

Define organic compound.This is a silly/strange representation of what organic compoundHow is this compound important to most life on Earth?How does this compound compare to an inorganic compound, like H2O?This difference is due to the flexibility of one type of atom… what is it?

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Macromolecules2–3 Carbon Compounds

Most organic compounds are macromolecules. What does this mean?Explain why are they macromolecules using the terms “monomers”, “polymer”, and “polymerization” (note the meaning of the prefixes, “mono” and “poly”).Are the monomers always identical?There are 4 major classes of organic compounds in living things, list them and know them.Which class is not considered a polymer?

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Carbohydrates2–3 Carbon Compounds

Define carbohydrate.What is the typical ratio of C:H:O and the generalized formula?What are the two major functions of carbohydrates in living things?Label the two example figures with what they represent in identity, mono- or poly- saccharide, and function.

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Study the figure and label the mono/poly-saccharides.Glucose is used by living things as a source of cellular ______?Starch, is a way for plants to ______ glucose..There is a similar form of “animal starch” stored in your muscles and liver known as _____?

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What are the monomers of carbohydrates called?Give 3 examples and where they are found.What is a disaccharide?Give 2 examples and where they are found.What are polysaccharides?Give 2 examples, along with where they are found and function.Note that the names of all carbohydrate molecules typically end in “ose” (Good to remember!).

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Lipids2–3 Carbon Compounds

What are the 4 classes of lipids?Lipids are composed mostly of which 2 elements?As a result, unlike water, they are not ______ and therefore not _____ in water, meaning they will not dissolve.This allows lipids to function as waterproof barriers, like cellular _____, and coverings, like the leaf _____.Describe the structure of a triglyceride using the terms glycerol and fatty acids.

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Lipids2–3 Carbon Compounds

Compare the two fatty acids. Identify 3 differences.The one on the left is _____ making it _____ at room temperature (fat).The one on the right is _____, making it _____ at room temperature (oil).Use this knowledge to describe a fatty acid that is polyunsaturated.

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Nucleic Acids

2–3 Carbon CompoundsWhy are nucleic acids called nucleic acids?Other than C, H & O, what 2 other elements are found in nucleic acids?What are the monomers of nucleic acids?What are the polymers of nucleic acids?What 3 compounds are bound together in one nucleotide?Between which two compounds are nucleotides bound in a polynucleotide?

Are they all the same?

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Nucleic Acids

2–3 Carbon Compounds

What is the general function of nucleic acids?What about their structure allows them to perform this function?What are the two major classes of nucleic acids, along with their acronyms?Describe 3 structural differences between them.

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Proteins2–3 Carbon Compounds

In addition to C, H, & O, what other element is found in all proteins?What are the monomers of proteins and how many different ones are there? What is the basis for this monomer name?What two parts are the same in each monomer and what part is different?What kind of bond joins monomers together?What are the polymers of proteins called?How do proteins compare in size and complexity to other organic compounds?

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AminoAcids

Protein Molecule


The information for arranging amino acids into polypeptides/proteins is stored in what molecule?What are 4 functions of proteins?What about their structure allows them to perform this variety of functions?

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The shape of a protein is known as its _____.The conformation of a protein depends on its _____ _____ _____.One _____ can function as a complete protein.Some proteins are made up of more than one _____, each considered a _____ of that protein.

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2–4 Chemical Reactions and Enzymes Chemical Reactions

Define chemical reaction.Label the chemical reactions represented in the photos.Compare the speed of these reactions.What is the significance or point of this comparison?

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2–4 Chemical Reactions and Enzymes Chemical Reactions

Chemical reactions break and reform _____.What are elements or compounds that enter into chemical reactions called and on which side of a chemical equation are they usually found?What are the elements or compounds produced by a chemical reaction called and on which side of a chemical equation are they found?In the example reaction, what are the reactants and what is the product?In the chemical equation, what do the numbers in front of the elements and compounds do for the equation?

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Energy in Reactions2–4 Chemical Reactions and Enzymes

Breaking and forming bonds requires changes in _____.Define exergonic reaction, and give an example.Define endergonic reaction and give an example.In order to stay alive, organisms must perform endergonic reactions. What is the ultimate source of energy for these reactions?Study the overall chemical equations for photosynthesis and cellular respiration. How are they related in terms of reactants and products?Trace the flow of energy from the ultimate source to the endergonic reactions keeping you alive.

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Identify and label the graphs representing an endergonic vs. exergonic reaction.The energy available for a reaction (y-axis) is _____ energy (heat).This increases the _____ energy (movement) of reactants.Note that BOTH endergonic and exergonic reactions require activation energy. Define activation energy.What characteristic of this type of graph can be used to identify endergonic vs. exergonic reactions?

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Some chemical reactions occur too slowly or have activation energies too high for living systems. Define enzymes, and explain how they solve this problem.Study the graph and relate what it illustrates to what enzymes are and do.Enzymes are very specific to the reactions they catalyze. How are they usually named? Give one example of an enzyme and the reaction it

catalyzes.

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Enzyme Activity

2–4 Chemical Reactions and EnzymesStudy this example of an enzyme catalyzed reaction and write the chemical equation using names, not chemical formulas.What are the reactants of an enzyme catalyzed reaction called?Note the region of the enzyme where the substrates “fit”. What is this region called and how is it important?What is a metaphor for how the substrates fit in the active site?Define enzyme-substrate complex.Note that the diagram is cyclical, illustrating that enzymes are _____!

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2–4 Chemical Reactions and Enzymes

E

Enzyme Activity

What are 2 environmental variables that can change the shape of the enzyme's active site so that it can not work?What is this called?Living cells can _____ enzymes with _____ that bind to the enzyme and change the shape of the active site (see diagram).

democritus (~2500ya)democritus (~2500ya) 2 subatomic particles 2-1 the nature of matter atomic facts...

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