Unit 2 Intro to Chemistry Flashcards
Describe the structure of an atom, and define the term isotope.
An Atom is the smallest unit of matter that retains the properties and characteristics of its element.
-Each Atoms is composed of a Nucleus
-The Nucleus is composed of Protons (positively charged ions) and neutrons (uncharged ions), and electrons (negatively charged ions).
-Electrons are found around the cell and seem to form a cloud around the nucleus. The number of protons is always equal to the number of electrons
-the atomic number is equal to the number of protons in a atom
-the atomic mass of an atom is the combination of protons and neutrons
Isotopes are the same element that contain the same number of protons of its original element however has a different number of neutrons in the nuclei.
What are the 4 main elements of the body?
Oxygen (O), Nitrogen (N), Carbon, Hydrogen
account for 96% of body mass
What elements make up 3.6% of body mass?
There are 8 elements:
Calcium (Ca), Phosphorus (P), Potassium (K), Sulfer (S), Sodium (Na), Chlorine (Cl), Magnesium (Mg), and Iron (Fe)
What are the Trace Elements that make up .4% of the body mass.
There are 14 elements:
Iodine (I), Aluminum (Al), Boron (B), Chromium (Cr), Cobalt (Co), Copper (Cu), Fluorine (F), Manganese (Mn), Molybdenum (Mo), Selenium (Se), Silicon (Si), Tin (Sn), Vanadium (V), Zinc (Zn).
Define ion
Ion: when an atom either gives up or gains an electron it becomes an ion. Which becomes either positively charged or negatively charged due to an unequal number of protons and electrons.
Describe the different types of chemical bonds, noting their relative strengths.
Ionic Bonds: Positively and Negatively charged atoms are attracted to one another this force is called Ionic bonds
When number of protons exceed the number of electrons it becomes a cation (a positively charged ion). If the number of Protons becomes less than the number of Elections is becomes a anion, (negatively charged ion)
These bonds are found in teeth, and bones. things that need great amount.
Covalent Bonds: Form by 2 atoms sharing 1, 2, or 3 pairs of their outer shell electrons. the more electron pairs made the strong the bond becomes.
most of the body tissues are made up of covalent bonds.
There are 2 types of covalent bonds,
Non-polar bond, when the sharing is equal among ions,
Polar covalent bonds are an unequal distribution one atom attracts another more strongly than the others.
Hydrogen bond: form when polar covalent bonds are present, when a hydrogen atom with a partial positive charge attracts the partial negative charge of a neighbouring electronegative atoms. usually oxygen or nitrogen.
These are the weakest from of bonds but helpful in creating temporary links btw molecules and larger molecules.
Describe the different forms of energy
Potential Energy : this is stored energy
Kinetic Energy : this is energy in motion
Chemical Energy : this is potential energy stored in bonds of molecules
Describe the types of chemical reactions.
Chemical Reactions breaking old bond requires energy and forming new bonds releases energy
There are 4 reaction types in the body
Synthesis Reactions: This is the process of 2 or more atoms, ions, or molecules forming into new and larger molecules
A + B —> AB
These are known as anabolism simple molecules become larger molecules
Decomposition Reactions : Here a molecule is split apart. Large molecules become smaller molecules, ions, or atoms.
AB —> A + B
Referred to as catabolism, breaking larger molecles into smaller units.
Exchange Reactions: This type of reaction is a mix of a sysnthesis reaction and decomposition reaction which break down from their original molecules and combine in a different way.
AB + CD —–> AD + CB
Reversible Reactions: These reactions are able to move from larger molecule to it’s simple molecules, ions, or atoms and back when special conditions are applied.
AB A + B
whatever is written above or below the line indicates what conditions are required for the reaction to occur.
Differentiate between organic and inorganic compounds.
There are 2 classifications of compounds in the body Inorganic and organic.
Inorganic Compounds: Usually lack carbon, are structurally simple, and are held together by ionic or covalent bonds. Ex are water, salt, acids, and bases.
Organic Compounds : always contain carbon, usually contain hydrogen, and always have covalent bonds. Ex are lipids, proteins, and carbohydrates, nucleic acids, and ATP
Discuss the properties of water.
There are 5 main properties of water. Makes up 55-60% of body mass in lean adults.
1) Excellent Solvent
-solvent is a liquid or gas in which some other materials called solute has been dissolved . The combination is called a Solution.
-Solutes that are charged or contain polar covalent bonds are Hydrophillic meaning they dissolve well in water.
-Molecules that are composed of mainly non-polar covalent bonds are hydrophobic, they are not very soluble in water.
2) Participates in chemical reactions
due to ability to dissolve many different substances it’s ideal for chemical reactions. Also active in decomposition and synthesis reactions.
3) Absorbs and releases heat very slowly
water is able to absorb and release a relatively large amount of heat with only a slight change in its own temperature.
4) requires a large amount of heat to change from a liquid to a gas
when water in sweat evaporates from the skin’s surface it requires a lot of heat to to do so, making it a great cooling mechanism.
5) Serves as a lubricant
helps organ cavities slide and move without wearing down, needed at joints where bones, ligaments, and tendons rub against one another.
Define the terms acid, base, salt, and ion.
Acid: a substance that breaks apart or dissociates into one or more hydrogen ions (H+) when it dissolves in water along with 1 or more anion
Base: a substance that usually dissociates into one or more hydroxide ions (OH-), when it dissolves in water along with 1 or more cations. A base also can be described as having the capacity to pick up one or more hydrogen (H+) ions. (Page 28)
Salt: When dissolved in water dissociates into cations and anions, neither or which is hydrogen or hydroxide.
Acids and bases react with one another to form salts.
HCL + KOH —> KCl + H2O
acid + Base —> salt + water
Ionization is the separation of inorganic acids, bases, and salts into ions in a solution.
Define pH, and explain the functioning of buffers.
In the body acids and bases must be balanced in the body for normal functioning.
Acids are formed from Hydrogen (H+), the more hydrogen ions in a solution the more acidic a solution is.
Bases are formed from hydroxide ions (OH-) the more basic (alkaline) a solution becomes.
pH is measures using the pH scale this is a scale from 0-14 where it measures the amount of hydrogen ions in a solution. 7 is the mid point where hydrogen and hydroxide ions are equal. Below 7 means more acidic, above 7 means more basic (alkaline) a change in of 1 on the pH scale represents 10x the number of hydrogen ions.
Buffers are chemical compounds that act quickly to temporarily bind H+, removing highly reactive, excessive H+ from a solution but not from the body.
List the subcategories of carbohydrates, and give examples for each subcategory.
Monosaccharides: Building blocks of carbohydrates. Ribose and deoxyribose are monosaccarides used to make ribonucleic acid (RNA) and Deoxyribonucleic acid (DNA)
Disacccharides: 2 simple sugars joined by a covalent bond. The monoscaccharides glucose and fructose combine to form the disaccharide sucrose (table sugar).
Polysaccharides: large carbohydrates composed of 10 or hundreds of monosaccharides joined through dehydration synthesis reactions. Glycogen is the main polysaccharide in the body. which is made entirely of glucose units joined together in long branching chains.
Identify and describe the subclasses of lipids, and distinguish between saturated and unsaturated fats.
Triglycerides: consists of a glyerol backbone and 3 fatty acid chains. These can be saturated, monounsaturated, and polyunsaturated.
Saturated fats only contain a single covalent bond btw carbon atoms
monounsaturated contain a double covalent bond btw 2 fatty acid carbon atoms
polyunsaturated contains more than 1 double covalent bond btw fatty acid carbon atoms.
Phospholipids: have a glycerol backbone and 2 fatty acids attached to the first 2 carbon atoms however the 3rd is a phosphate group. that links small charged group to the glycerol backbone. these form much of the membrane that surrounds each cell.
Steroids: have a 4 ring structure of carbon atoms
Describe the structure of amino acids and proteins.
-Amino Acids are the building blocks of all proteins.
-They are made up of an amino group (-NH2) at one end
-a carboxyl group (-COOH) at the other end.
-each of the 20 amino acids has a different side chain (R group).
The covalent bonds that join amino acids together are called peptide bonds.
