2.1 The Nature of Matter
What are the three primary parts of an atom, what are the charges on these three primary subatomic particles, and where are each of these found?
Protons - positive charge, found in the nucleus
Neutrons - neutral charge (1.0), found in the nucleus
Electrons - negative charge, found surrounding the nucleus
What are the properties that make water unique?
Polarity, Cohesion, Adhesion, Hydrogen Bonding
What makes carbon so chemically interactive that in turn causes it to be so special in the chemistry of life?
Carbon can bond with many elements including hydrogen, oxygen, phosphorus, sulfur, nitrogen to form the molecules of life
What are the reactants and products in a chemical reaction?
Reactants-Elements or compounds that enter a chemical reaction
Products- Elements or compounds produced by a chemical reaction
Why are the basic chemistry of atoms considered to be electrically neutral?
They have the same number of protons and electrons
What makes water's unique properties so essential to life?
Polarity: Water has a partial negative charge on one end and partial positive charge on the other (polar=(+) or (-)
Cohesion: Is an attraction between molecules of the same substance; Causes water molecules to be drawn together (also produces surface tension so we insects or spiders can walk on ponds)
Adhesion: Is an attraction between molecules of different substances
Hydrogen Bonding: Give one life’s most important molecules many of its unique characteristics; Also explains waters ability to dissolve so many other substances, which is a property essential in living cells
What are the primary elements and compounds that compose the majority of all of life’s organisms?
Carbon, Hydrogen, Oxygen, Phosphorus, Sulfur, Nitrogen
What is a chemical reaction? What causes a chemical reaction?
A process that changes, or transforms, one set of chemicals into another. This is caused when two molecules collide with the right orientation and sufficient force
Where does the name “atom” originate?
Greek word atomos which means “unable to be cut”
Explain polarity and the reason why water is a polar substance?
Polarity-a molecule in which the charges are unevenly distributed
Water is a polar substance because it has a negative charge on one side and positive charge on the other
What is the relationship between a monomer and a macromolecule?
Macromolecules are made from monomers
Explain activation energy and how it influences a reaction.
Energy that is needed to get a reaction started. It influences a reaction so that reactants can move together
What two particles make up the atom's mass?
Protons and neutrons
Explain why water's polarity makes it a “universal solvent”?
Because it has hydrogen which has a positive charge and oxygen which has a negative charge which allow the water molecules to become attracted to different types of molecules
What does polymerization have to do with the previous question?
Polymerization is the process of turning monomers to macromolecules
Compare and contrast an endothermic with an exothermic reaction.
Exothermic-absorbs heat
Exothermic- releases heat
Both are changes where the heat is present
Valence electrons are able to participate in bonding and seek a shared pairing, why are they considered stable once the valence electrons have paired?
Because they have the total electrons they need
Explain what a polar bond is and why water has 4 as a liquid and only 3 as a solid?
Oxygen attracts the shared electrons more strongly than hydrogen, so one side of the water molecule has a partial positive charge and the other side has a partial negative charge.
Identify the monomers found in the 4 basic compounds that compose life?
Glucose, Glycerol & Three fatty acids, Amino Acids, Nucleotides
What does an enzyme do and how does it do it?
Lowering activation energy by binding to reactant molecules and holding them so that the chemical bond breaks
What is the name for the number of protons in an atom?
Atomic number
Explain why this difference in polar bonds impacts water's density and the importance of this unique change in density?
Water is denser when frozen because of fewer polar bonds
Identify how the 4 basic compounds are used in your body?
Carbohydrates, Lipids, Proteins, Nucleic Acids
How does an enzyme influence activation energy?
Enzymes speed up reactions by lowering activation energy
What happens if the number of protons changes?
You are changing the atom from one element to a different element
Explain why your liquid drink will climb a short distance up your straw all on its own?
Adhesion between water molecules and glass molecules causes water to rise in a narrow tube against the force of gravity – this is called capillary action.
What is the ratio of elements found in carbohydrates?
1:2:1
What causes a shape change in an enzyme and how does this impact the chemical reaction that the enzyme is involved in?
An enzyme changes shape when it binds its substrate, which results in an even tighter fit. It brings two substrates together in the right orientation
What happens when the number of neutrons in an atom changes, and why do these all have the same chemical properties?
It creates an isotope. They have the same number of electrons so they have the same chemical properties.
How does an insect walk on water?
Because of adhesion which produces surface tension which allows insects to walk on water
Which organic compound, pound for pound, contains the greatest amount of energy?
fats
What does it mean to be “radioactive”, and how do we use radioactive in a positive manner?
Their nuclei (nucleus) are unstable and break down (at a constant rate over time)
Can be used to detect and treat cancer and destroy cancer and kill bacteria that causes food to spoil; Tracers to follow the movements of substances within organisms
How does the hydrogen bonding of water give it a high heat capacity, and how does this impact life?
It takes a large amount of heat energy which causes those molecules to move faster which raises the temp of water to rise.
What is a lipid saturated with and what do you look for to know if the lipid is saturated, unsaturated, or polyunsaturated?
Fatty acids
Saturated: If there only one single bond between the carbons in hydrocarbon chain
Unsaturated: When the hydrocarbon chain has a double bond
Polyunsaturated: Lipids whose fatty acids contain more than one double bonds
Compare and contrast a compound and a mixture and provide examples of each?
Compound (substance formed by chemical combination of two or more elements in definite proportions ex: Water (contains two atoms of hydrogen for each atom of oxygen: H20
Mixture (material composed of two or more elements or compounds that are physically mixed together but not chemically combined) Ex: Salt/pepper
Compare: both are composed of two or more elements
Contrast: Compound is formed by chemical combination; Mixture is formed by physically mixing the elements/compounds together and is not chemically combined
Compare and contrast solutions and suspensions and provide examples of each?
Solutions: Universal Solvent; Ions are evenly distributed throughout the solution
Suspensions: Blood; Movement keeps larger particles afloat throughout the fluid
What are the three parts of the monomer that makes nucleic acids? Which of these three parts is interchangeable and thus creates 20 different amino acids?
A phosphate group, A 5 carbon sugar, A nitrogenous base
5 carbon sugar
Do compounds act the same as the elements that compose them?
No they are very different from the elements
What is an ion?
Positive and negative charged atoms
How is it that the body can get millions of proteins from just 20 different amino acids?
Proteins have amino acids as their building blocks
What is the smallest unit of a compound?
Molecule
What molecule or elemental ions cause pH levels to change?
Hydrogen ions
Of the two types of bonds we discussed, which shares electrons and which transfers them?
Ionic Bonds- transfers electrons
Covalent bonds- shares electrons
What is the range of the pH scale? On the pH scale, how much more basic is 7 as compared to 4?
0-14
1000 times more basic
Electrons are not equally shared in covalent bonding. What is it called when one atom has a stronger affinity (pull or hold) for the “shared” electrons?
Ionic bond because it has a stronger electronmagnivity
What causes pure water to be neutral at a pH of 7? Is normal rain acidic or basic and how much more acidic is acid rain?
When the concentration of H+ ions and OH- ions is equal
Acidic, 10 times greater
What does a buffer do and how does it do it?
Weak acids or bases that can resist pH change by reacting with strong acids or bases. This helps maintain homeostasis.