BIOL 1406 Discussion Questions Basic Chemistry 1 Explain the structure of an atom 2 Draw diagrams of the 5 atoms described below For each atom use a circle to represent the nucleus and inside the circle write down how many protons and neutrons the nucleus contains e g 9p 10n Use concentric circles around the nucleus to represent the energy levels of the atom and next to each circle write down the number of electrons in that energy level e g 2e A B C D E atomic number 1 atomic mass 1 overall charge 0 atomic number 7 atomic mass 15 overall charge 0 atomic number 11 atomic mass 23 overall charge 0 atomic number 11 atomic mass 23 overall charge 1 atomic number 17 atomic mass 35 overall charge 1 3 Explain the difference between an element a compound and a mixture and give an example of each 4 Explain how the following types of bonds are formed and give an example of each A ionic bond B covalent bond C hydrogen bond 5 Draw diagrams of the following molecules A water B molecular hydrogen C molecular oxygen D methane E ammonia F carbon dioxide 6 a What is the driving force for bonding in a hydrogen bond versus a covalent bond b Which is stronger Explain why in terms of the electrical attractions involved 7 Consider a hypothetical atom with an atomic number of 4 and a net electronic charge of 1 How many neutrons does this atom have Will it form ionic or covalent bonds Defend your answer 8 Evaluate the following statement Potassium atomic number 19 mass number 40 and sodium atomic number 11 mass number 23 have similar chemical properties and reactive behavior 9 Copper has an atomic number of 29 and a mass number of 64 What would result if an uncharged copper atom lost two electrons a The atom would have a double negative charge and be an ion b The atomic number of the atom would remain 29 the mass number would be reduced to 62 and the atom would be an anion c The atomic number would remain 29 the mass number would increase to 66 and the atom would be a cation with a 2 charge d The atomic number would be reduced to 27 the mass number would remain 64 and the atom would be an anion with a 2 charge e The atomic number would remain 29 the mass number would remain 64 and the atom would be a cation with a 2 charge 10 a How many atoms or molecules does one mole of an element or compound contain b What is the weight of 1 mole of pure sodium Na c How many molecules of Na are in 1 mole of Na d How would you determine how many grams are in a mole of any chemical element or compound 11 a State the differences in solubility for O2 and NH3 b What is the basis for this difference c In reaching your answer draw the structures of the molecules as valence shell diagrams Given these diagrams consider the types of interactions each molecule could have with water 12 The molecule diagrammed here can also be represented by the formula CH3COOH Label each bond of this molecule as polar or nonpolar covalent bonds ionic bonds hydrogen bonds and van der Waals interactions Explain why you chose your answers 13 Ligands such as insulin bind to their receptors in a reversible manner What properties of non covalent bonds enable such interactions 14 Atoms can be represented by simply listing the number of protons neutrons and electrons for example 2 p 2 n0 2 e for helium Which atom represents the 18O isotope of oxygen 15 Review the valences of carbon oxygen hydrogen and nitrogen and then determine which of the following molecules is most likely to exist 16 Explain why potassium atomic number 19 mass number 40 and sodium atomic number 11 mass number 23 have similar chemical properties and reactive behavior 17 Atom X has an atomic of 6 Predict the molecule that would form if atom X were able to react with hydrogen Draw the molecule and explain your reasoning 18 Diagram an H2O molecule interacting with an NH3 molecule Identify what types of bonds are present within each molecule and between the molecules a b c d Which drawing depicts the electron configuration of neon Which drawing has a valence of 3 Which if any drawings will be able to from an ionic bond Which if any drawings will be able to form a covalent polar or non polar bond 19 Using the terms below Option 1 Create a concept map using http ctools msu edu ctools index html Option 2 Create a working model using materials provided Be prepared to share with the class anion element orbital atom energy periodic table of the atomic mass energy level elements atomic nucleus hydrogen bond polar covalent bond atomic number ion potential energy cation ionic bond product chemical bond ionic compound proton chemical equilibrium isotope radioactive isotope chemical reaction mass number reactant compound matter salt covalent bond molecular formula structural formula dalton molecule trace element electron neutron valence electron shell nonpolar covalent bond valence electron electronegativity 20 Acid precipitation has lowered the pH of a particular lake to 4 0 What is the hydrogen ion concentration of the lake Hydroxide ion concentration 21 Draw the atomic structure of the following molecules or compounds Show electron shells and electron placement in bonding Then rank the bonds from strongest to weakest CH4 H2O NaCl O2 bonding between 2 molecules of H2O 22 When the pH of a solution shifts from 7 to 3 how has the hydrogen ion concentration changed 23 a Is the molecule below hydrophilic or hydrophobic Explain your answer b If you add the molecule below acetic acid to water and raise the concentration of H ions to 10 4 what is the pH of this solution 24 Life as we know it could not exist without water All the chemical reactions of life occur in aqueous solution Water molecules are polar and are capable of forming hydrogen bonds with other polar or charged molecules As a result water has the following properties A H2O molecules are cohesive they form hydrogen bonds with each other B H2O molecules are adhesive they form hydrogen bonds with polar surfaces C Water is a liquid at normal physiological or body temperatures D Water has a high specific heat E Water has a high heat of vaporization F Water s greatest density occurs at 4 C Explain how these properties of water are related to the phenomena described in parts a h below More than one property may be used to explain a given phenomenon a During the winter air temperatures in the northern United States can remain below 0 C for months however the fish and other animals living in the lakes survive b Many substances for example salt NaCl