Chapter 2- Chemistry BISC306
Classify each statement or molecule as a polar bond or nonpolar bond. Nonpolar bonds
-the bond between hydrogen atoms in diatomic hydrogen (H2) -the bond between nitrogen atoms in diatomic nitrogen (N2) -electrons of adjoined atoms are equally distributed between those atoms -electrons are equally shared between atoms in a covalent bond
Classify each statement or molecule as a polar bond or nonpolar bond. Polar bonds
-the bond between oxygen and hydrogen in water (H2O)-electrons are not equally shared by the atoms in a covalent bond -one atom has a partial negative charge, and the other atom has a partial positive charge -the atoms in a covalent bond have partial charges
An atom of oxygen has eight protons, eight electrons, and eight neutrons. What is the atomic mass of the oxygen atom? 16,16, because the oxygen atom has 8 protons 8 protons and 8 neutrons8 neutrons8, 8, because the oxygen atom has 8 electrons8 electrons24, 24, because the oxygen atom has 24 subatomic particles24 subatomic particles8, 8, because the oxygen atom has 8 protons
16,16, because the oxygen atom has 8 protons8 protons and 8 neutrons
Use the atom builder interactive to arrange each atom or ion by mass number. Largest mass number 4 protons (p), 3 Neutrons (n), 4 electrons (e) 2p,4n,2e 2p,2n,2e 1p,2n,2e 2p,1n,1e
4 protons (p), 3 Neutrons (n), 4 electrons (e) 2p,4n,2e 2p,2n,2e 1p,2n,2e 2p,1n,1e
What is the typical pH of biological fluids in humans, such as blood and extracellular fluid? 12.3 7.4 19.2 5.4
7.4
What is the cellular importance of ATP? ATP is the primary source of chemical energy. ATP buffers weak acids to prevent pH changes. ATP is an essential amino acid in cell proteins. ATP is one of the two purine nucleotides in DNA.
ATP is the primary source of chemical energy.
The strength of an acid or base is indicated by pHpH , a measurement of the concentration of hydrogen atoms in the solution. Classify each substance as acidic, neutral, or basic using the provided pHpH scale.
Acid = lemon juice and grapefruit juice Neutral = pure water Base = baking soda and drain cleaner
Which of the reactions is a decomposition reaction? 2C2H6(g)+7O2(g)⟶6H2O(l)+4CO2(g)2C2H6(g)+7O2(g)⟶6H2O(l)+4CO2(g) 2Al(s)+4Cl2(g)⟶2AlCl3(s)2Al(s)+4Cl2(g)⟶2AlCl3(s) BaCO3(s)⟶BaO(s)+CO2(g)BaCO3(s)⟶BaO(s)+CO2(g) Mg(s)+HCl(aq)⟶MgCl2(aq)+H2(g)
BaCO3(s)⟶BaO(s)+CO2(g)
Which of these molecular formulas is a carbohydrate? C14H28O2C14H28O2 C5H11NO2SC5H11NO2S C8H16C8H16 C3H6O3C3H6O3 C8H11NO2
C3H6O3
Biomolecules are organic molecules that are produced by living organisms to perform a variety of functions. Classify each of the biomolecules as a carbohydrate, lipid, nucleic acid, or protein. Carbohydrates Lipids Nucleic acids Proteins
Carbohydrates - glucose and glycogen Lipids- cholesterol and estrogen Nucleic Acids - DNA and RNA Proteins - enzyme and hemoglobin
During photosynthesis, the cell forms C6H12O6C6H12O6 (glucose) and O2O2 (oxygen gas) by combining CO2CO2 (carbon dioxide) and H2OH2O (water). Classify the molecules as reactants or products in the chemical reaction. Reactants
Carbon Dioxide water
Match the correct definition to each type of bond. Covalent Ionic Hydrogen
Covalent- a bond in which atoms share electrons Ionic - a bond involving electron transfer between two atoms Hydrogen - an attraction between hydrogen and an electronegative atom
Classify the traits of eukaryotic nucleic acids as typical of DNA only, RNA only, or both. DNA only RNA only Both
DNA only - uses thymine, double stranded RNA only - uses uracil, single stranded Both - contains codes for proteins, made up of nucleotides
You recently diagnosed Mr. Vasiliev with Creutzfeldt-Jakob Disease (CJD), a neurodegenerative disease caused by prions. Abnormal prions aggregate in the brain and cause cell death. Mr. Vasiliev's family is trying to learn more about CJD and prions. You explain that prions are proteins that are misfolded or deformed. What term describes the general disruption of protein structure? denaturation diffusion condensation acidification
Denaturation
Classify each phrase as describing an enzyme, an active site, or a substrate. Enzyme Active site Substrate
Enzyme = a biological catalyst, a protein containing an active site. Active site = a specific enzyme location that binds with the substrate Substrate = a substrate that the enzyme acts upon, may be a phosphate group
How do enzymes catalyze reactions? Enzymes change the free energy of the products. Enzymes carry out a reaction without needing reactants. Enzymes are consumed by a reaction to catalyze it. Enzymes increase the activation energy of a reaction. Enzymes bind with and change the conformation of substrates.
Enzymes bind with and change the conformation of substrates.
Which of the statements regarding potential energy is true? An object in motion does not have any potential energy. Potential energy is the energy that an object has based on its position. Potential energy cannot be stored and is immediately converted to kinetic energy. The potential energy of an object cannot be determined.
Potential energy is the energy that an object has based on its position.
Mr. Vasiliev, recently diagnosed with Creutzfeldt-Jakob Disease (CJD), and his family are trying to learn more about his disease. CJD occurs because naturally occurring prion proteins become misfolded and accumulate in the brain, forming plaques. Some studies indicate that prion accumulation could occur because alpha helices form in the prion proteins instead of beta sheets. You explain protein structure levels to the family. Alpha helices and beta sheets are components of which level of protein structure? quaternary primary secondary tertiary
Secondary
Classify each mixture as a solution, suspension, or colloid. Solution Suspension Colloid
Solution - air and urine Suspension - mud and blood Colloid - milk and smoke
Which of the statements describe hydrogen bonding between water molecules or describe properties of water that lead to hydrogen bonding between water molecules? The slightly negative oxygen atom of one water molecule is attracted to the slightly positive hydrogen atom of another water molecule. The slightly positive hydrogen atom is attracted to the slightly negative oxygen atom within a single water molecule. A water molecule is nonpolar because it has a linear structure and its shared electrons are equally attracted to the oxygen atom and the hydrogen atoms. A water molecule is polar because it has a bent structure and its shared electrons are more attracted to the oxygen atom than the hydrogen atoms.
The slightly negative oxygen atom of one water molecule is attracted to the slightly positive hydrogen atom of another water molecule. A water molecule is polar because it has a bent structure and its shared electrons are more attracted to the oxygen atom than the hydrogen atoms.
Which of the statements accurately describes elements? They cannot be broken down by chemical means. They are pure substances. They are chemical combinations of simpler forms of matter. They can be broken down by physical means. They combine chemically to form new substances; they are "building blocks of matter".
They cannot be broken down by chemical means. They are pure substances. They combine chemically to form new substances; they are "building blocks of matter".
Olive oil, which is a liquid at room temperature, is used in cooking pasta. Coconut oil, which is a solid at room temperature, can be used as an alternative to butter. Butter, which is a solid at room temperature, is often used in cooking. The oil inside flaxseed oil pills is liquid at room temperature. Answer Bank saturated unsaturated
Unsaturated Saturated Saturated Unsaturated
Which of the given substances can be classified as a compound? carbon (C)(C) water (H2O)(H2O) sucrose (C12H22O11)(C12H22O11) diamond (C𝑛)(Cn) nitrogen gas (N2)(N2) table salt (NaCl)
Water Sucrose Table Salt
How does evaporation help regulate body temperature? When sweat evaporates, heat is removed from the skin, which cools the body. When sweat evaporates, heat is absorbed by the skin, which warms the body. Sweat creates a barrier on the skin that traps heat within the body. Evaporation of sweat cools the body by reducing the body's electrolyte concentration. Sweating reduces the volume of water in the body which causes the body to cool down.
When sweat evaporates, heat is removed from the skin, which cools the body.
What is a peptide bond? an ionic bond formed when a nitrogen atom in one molecule reacts with a carbon atom in a different molecule an ionic bond formed when the hydroxyl group of one molecule reacts with an amino group of a different molecule a covalent bond formed when a nitrogen atom in one molecule reacts with an oxygen atom in a different molecule a covalent bond formed when the carboxyl group of one molecule reacts with an amino group of a different molecule
a covalent bond formed when the carboxyl group of one molecule reacts with an amino group of a different molecule
Which of the samples are composed of matter? air inside a balloon? ice on a pond fog in the morning warmth from a fire sound of a birdsong
air inside a balloon ice on a pond fog in the morning
Mr. Vasiliev is a 63‑year‑old man who has recently started presenting symptoms of dementia, such as memory loss, trouble reasoning, and impaired speaking. After extensive testing, you have diagnosed Mr. Vasiliev with Creutzfeldt-Jakob Disease (CJD). CJD is a rare neurodegenerative disease caused by misfolded proteins, called prions, that form plaques and kill neurons in the brain. Mr. Vasiliev's family wants to know more about CJD and how the disease occurs. You start by explaining general protein structure. Proteins consist of which type of monomer? monosaccharides nucleotides fatty acids amino acids
amino acids
What is the difference between an anion and a cation? an anion has no charge whereas a cation has a positive charge an anion has a negative charge whereas a cation has a positive charge an anion has a positive charge whereas a cation has a negative charge an anion has a negative charge whereas a cation has no charge
an anion has a negative charge whereas a cation has a positive charge
What are the monomers, or building blocks, of a protein? monosaccharides nucleotides fatty acids phospholipids amino acids
animo acids
From what substance are steroid hormones synthesized? cholesterol tyrosine protein triglyceride
cholesterol
When cells link monomers together to construct polymers, which process is used to make the monomers form bonds with each other? cohesion dissolution hydrolysis dehydration evaporation
dehydration
What functions do salts perform in the body? increase pH by accepting H+H+ ions facilitate action potentials in neurons participate in dehydration synthesis reactions easily dissociate into ions that are electrolytes
facilitate action potentials in neurons easily dissociate into ions that are electrolytes
Carbohydrates, or saccharides, are classified into three main types according to their structure: monosaccharides, disaccharides, and polysaccharides. Identify the pair of monosaccharides. glucose and starchlactose and galactose fructose and galactose glycogen and sucrose
fructose and galactose
Classify the examples of kinetic energy or potential energy. Examples of potential energy
gasoline sitting in a gas can a stretched rubber band water held behind a dam
During photosynthesis, the cell forms C6H12O6C6H12O6 (glucose) and O2O2 (oxygen gas) by combining CO2CO2 (carbon dioxide) and H2OH2O (water). Classify the molecules as reactants or products in the chemical reaction. Prodcuts
glucose oxygen
Activation energy is best defined as the energy that is used to make new chemical bonds and form products. is required to bring the reactant molecules to a transition state. is required to form products that are at a higher energy than the reactants. is released when an enzyme binds its specific reactant molecules. is transferred to the products at the end of the reaction.
is required to bring the reactant molecules to a transition state.
More than 96% of the human body is composed of four main elements. Which of the elements are included in that list? nitrogen oxygen carbon sodium calcium
nitrogen oxygen carbon
A buffer is a substance that absorbs hydrogen ions if a solution becomes too basic. releases or accepts hydrogen ions to maintain pH. converts excess hydroxide ions into hydrogen ions to maintain pH. releases hydrogen ions if a solution becomes too acidic.
releases or accepts hydrogen ions to maintain pH.
Choose the best description of kinetic energy. energy that spontaneously becomes more ordered heat that is lost or gained in a reaction the energy an object has as a result of its own movement the energy an object has due to its position
the energy an object has as a result of its own movement
Classify the examples of kinetic energy or potential energy. Examples of kinetic energy
water falling down a waterfall a rubber band short through the air wind blowing through a windmill