Chapter 2 Study Guide PDF

**Chapter 2** You can use this outline to take notes from your reading or from lecture. You can refer to your textbook for more detailed information on these topics. **[Chemistry Fundamentals:]** 1. **Define matter:** is anything that has weight (mass) and takes up space (living and nonlivin...

**Chapter 2** You can use this outline to take notes from your reading or from lecture. You can refer to your textbook for more detailed information on these topics. **[Chemistry Fundamentals:]** 1. **Define matter:** is anything that has weight (mass) and takes up space (living and nonliving things). 2. Define Elements a. **List the four elements that make up 95% of the human body:** Oxygen, Carbon, Hydrogen, Nitrogen 3. **Define atoms:** are the smallest unit of an element 4. **Describe the structure of atoms:** An atom consists of a central nucleus containing protons and neutrons, and electrons in orbit around the nucleus in shells. 5. List the 3 subatomic particles; the location of each in the atom; if applicable the charge of each; if applicable the weight of each. **Protons**: have a **positive** charge and are about equal in size to neutrons. Location: in the nucleus of an atom **Neutrons:** are **uncharged**. Location: inside the nucleus of every atom **Electrons**: are much smaller than protons and neutrons and have a **negative** charge. Location: surrounding the nucleus in a region called the electron cloud 6. **Define ion:** Atoms that gain or lose one or more electrons become charged a. **Define cation:** are ions that are positively charged. b. **Define anion:** ions that are negatively charged 7. **Define atomic number:** the number of protons in the atoms of an element 8. **Define atomic weight and explain how is it calculated** 9. **Define isotope:** Atoms with the same atomic number, but different mass numbers **[Chemical Bonds]** 1. **Which subatomic particle determines the bonding behavior of an atom?** The electron 2. **Explain the shells of an atom and the maximum number of electrons in each shell.** Electrons revolve around the nucleus in a specific circular path known as orbit or called a shell. The first shell can hold up to two electrons, the second shell can hold up to eight electrons, the third shell can hold up to 18 3. **Explain the activity of electrons in ionic bonding** Electrons are given to other atoms/received from other atoms 4. **Explain the activity of electrons in covalent bonding** Each atom contributes one electron to each shared pair and effectively gains an additional electron from the shared pair. 5. **Explain the activity of electrons in polar covalent bonding** electrons are not shared equally between atoms due to differences in electronegativity 6. **Explain hydrogen bonding between molecules. Which types of atoms are usually involved with polar bonding?** Forms from the relatively weak attraction between the slightly positive "H" end of a polar molecule and the slightly negative "N" or "O" end of a nearby polar molecule Atoms with significantly different electronegativities, usually between two nonmetal atoms where one has a much higher electronegativity than the other; common examples include bonds between hydrogen and oxygen, carbon and oxygen, or nitrogen and hydrogen 7. **Explain what the letters and numbers represent in a molecular formula such as C~6~H~12~O~6~** The letters represent the chemical elements present (Carbon - C, Hydrogen - H, Oxygen - O), while the numbers following each element symbol indicate how many atoms of that element are present in one molecule of the compound; so, in this case, one molecule of glucose (C6H12O6) contains 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms 8. **Structural formulas:** use single lines to illustrate single bonds, double lines represent double bonds, etc. **[Chemical Reactions]** 1. **Synthesis reactions** a. **Uses of synthesis reactions:** to create new, more complex compounds from simpler reactants b. **Examples** A+B \-\--\> AB 2. Decomposition reactions a. Uses of decomposition reactions: larger molecules (such as food molecules) are broken into smaller ones, by breaking chemical bonds: b. Examples AB\-\--\>A+B 3. **Exchange reactions** (such as acid-base reactions) occur as parts of molecules switch places, by breaking chemical bonds and forming new ones AB+CD\-\-\--\> AD+CB 4. **Reversible reactions:** Are ones in which the products can change back into the reactants; they are symbolized by using double arrows: AB+CD\AD+CB 5. **Catalysts:** influence the speed of chemical reactions without being used up in the process; catalysts in the body are called enzymes. **[Chemicals]** **[Electrolytes]** 1. **Definition of Electrolytes** Substances that release ions in water 2. **Types of Electrolytes** a. Salts b. Acids: Electrolytes that release hydrogen ions in water c. Bases: Electrolytes that release ions that combine with hydrogen ions in water **[pH Scale]** 1. **The pH scale is a logarithmic scale. Explain the term logarithmic scale.** a method of displaying data where the intervals between values increase exponentially 2. Explain the values 0, 7 and 14 on the pH scale. A pH in the range of 0 to \7 to 14 indicates the presence of more hydroxide ions than hydrogen ions and is considered **basic or alkaline**. The higher the pH, the more basic the solution is. 3. **Buffers:** are chemicals that combine with excess acids or bases to help minimize pH changes in body fluids 4. **Acidosis:** a condition where the body fluids become too acidic 5. **Alkalosis:** a condition in which the body\'s fluids become too alkaline (basic). **[Inorganic Chemicals]** 1. **Definition of inorganic chemicals**: typically a chemical compound that lacks carbon--hydrogen bonds⁠‍, usually dissolve in water and release ions, making them electrolytes 2. **Water:** is the most abundant compound in living things, and makes up two-thirds of the weight of a human adult a. **Solvent** is a substance in which other substances dissolve b. **Solute** dissolved substances 3. **Oxygen** 4. **Carbon dioxide** released as a waste product during energy-releasing metabolic reactions; expired from the lungs 5. **Salt** - Compounds consisting of oppositely charged ions - Salts provide necessary ions, such as sodium, chloride, potassium, calcium, magnesium, phosphate, carbonate, bicarbonate, and sulfate - These electrolytes play important roles in many of the body\'s metabolic processes, such as nerve impulse conduction, muscle contraction, and transport of substances across cell membranes **[Organic Chemicals]** 1. **Definition organic chemicals** 2. **Carbohydrates (CHO):** Provide energy for cellular activities and materials for synthesizing various cell structures; stored as energy reserves **Monosaccharides** (simple sugars) he smallest carbohydrates; contain 5 to 6 C atoms; examples: glucose, fructose, galactose, ribose, deoxyribose **Disaccharides** (double sugars): consist of 2 simple sugars; examples: lactose, sucrose, maltose **Polysaccharides** (many simple sugars): consist of many glucose molecules joined together; examples: glycogen, starch 3. **Lipids** Are organic substances that are insoluble in water a. Triglycerides: are the most abundant type of lipids b. Triglycerides store and supply energy for cellular function c. Triglycerides, like carbohydrates, consist of carbon, hydrogen, and oxygen, but have a smaller proportion of oxygen atoms than carbohydrates - **Fatty acids (FA)** and **glycero**l: **fatty acid** is a long hydrocarbon chain with a carboxyl group at one end, while **glycero**l is a small organic molecule with three hydroxyl groups - **Saturated FA:** Fatty acids with all single carbon-carbon bonds - **Unsaturated FA:** Those with one or more double bonds between carbon atoms d. **Phospholipids:** Consist of glycerol, two fatty acids, and a phosphate group The phosphate "head" is hydrophilic and the fatty acid "tail" is hydrophobic Important in cellular structures, such as plasma membranes e. **Steroids:** Complex structures containing four carbon rings, A very important steroid is cholesterol, which is used to synthesize the sex hormones and several hormones from the adrenal glands 4. **Proteins:** are organic compounds containing C, O, H, and N (nitrogen) atoms; some also contain S (sulfur) a. **Amino acids**: Proteins consist of building blocks b. **Conformation:** Unique 3-dimensional shape of a protein, due to hydrogen and covalent bonding in different parts of the polypeptide chain Determines the function of a protein Can be long and fibrous or globular A slight, reversible change in conformation can be part of a protein's normal functioning c. Denatured proteins: Irreversible disruption of a protein's shape, and loss of function, due to breaking of hydrogen bonds Caused by pH changes, excessive temperature changes, radiation, or chemicals Example: Hard-boiling of an egg denatures the albumin 5. **Nucleic Acids**: Form genes and participate in protein synthesis, Large organic molecules a. **Nucleotides:** Building blocks containing carbon, hydrogen, oxygen, nitrogen, and phosphorus b. **RNA** - ***[ribonucleic acid): ]*** - Single-stranded - Functions in protein synthesis - Nucleotides contain the sugar, ribose **Adenosine triphosphate (ATP):** A modification of RNA that contains three phosphate groups Stores and provides energy for chemical reactions in the body c. **DNA** - **(deoxyribonucleic acid):** - Double-stranded, twisted into a spiral, held together with hydrogen bonds - Stores the molecular (genetic) code in genes, which is used by cells to synthesize proteins - Nucleotides contain the sugar, deoxyribose