Chem 120 final exam 114 questions with 100% correct answers Latest Updated, Exams of Chemistry

Download Chem 120 final exam 114 questions with 100% correct answers Latest Updated and more Exams Chemistry in PDF only on Docsity! Chem 120 final exam 114 questions with 100% correct answers Latest Updated What is the correct order of melting points for the following alkanes, from highest to lowest temperature? - Correct answerheptane > hexane > ethane > methane 2. Given an alkane that contains 25 carbon atoms. How many hydrogen atoms are present in its structure? a) - Correct answer) 52 3. Which of the following properly describes constitutional (structural) isomers? - Correct answercompounds with the same molecular formula, but a different order of attachment of atoms 4. How many secondary and tertiary carbons, respectively, are in the following compound? - Correct answer) 2, 3 5. What is the molecular formula and name of the following compound? - Correct answerC4H9Cl, 2-chlorobutane 6. What is the IUPAC name of the compound below? - Correct answermethylcyclohexane which reaction type is most characteristic of alkenes? - Correct answeraddition what is the IUPAC name for the compound below? - Correct answertrans- 2, 3- dichlorvos-2-pentene what is the structure and name of the product of the following reaction? - Correct answerch3ch2ch2ch3, butane alkanes and alkenes are no polar compounds and hence have poor solubility in water - Correct answertrue carbon monoxide may be produced in the incomplete combustions of methane. - Correct answertrue The names ortho- dimethylbenzene and 1,4- dimethylbenzene represent the same compound - Correct answerfalse if a compound's name ends with " diene", this suggest that is it an alkene containing two double bonds in its structure - Correct answertrue what is the oxidation of a primary alcohol - Correct answeraldehyde which of the following alcohol is tertiary alcohol? - Correct answer2- methyl- 2- butanol what compound is produced when 2 methyl-3 pentanol is oxidized ? - Correct answer2 methyl- 3 pentanone what class of compounds is represented by the general formula R-O-R - Correct answerethers which of the following compounds will give a silver mirror finish when treated with tollens' reagent ? - Correct answerbutanal which is the IUPAC name for the following compounds - Correct answer2-chloro, 3- hexanol what is the proper IUPAC name for the three carbon aldehyde - Correct answerpropanal what class of compounds is commonly used as a medical anesthetic - Correct answerethers a phenol is a compound that contains a hydroxyl group attached to a benzene ring - Correct answertrue by definition oxidation is a process that involves removal of hydrogens - Correct answertrue The oxidation of a ketoneproduces a carboxylic acid - Correct answertrue 14. Small (low molecular weight) aldehydesare generally lesswater-soluble than large ones - Correct answertrue 1. You are given fourdifferentcompounds(A, B, C, and D)that havecomparable weights:Compound A:etherCompound B:ketoneCompound C:alcoholCompound D:alkaneD, A, B, C b) Briefly explain your answer. (1 pt) - Correct answerD, A, B, C The highest b.pamong the four given compound is that of alcohol. Alcohols are able to hydrogen-bond to each other and hence making the interactions between them stronger and require higher energy to break apart. On the other hand, alkanes have the lowest b.p because they have no ability to hydrogen bond. 11.How does the melting point of an unsaturatedfatty acid compare to that of a saturatedfatty acid with an equal number of carbon atoms? - Correct answerb) The melting point of the unsaturated fatty acid will be lower than that of the saturated fatty acid. A laboratory sample containsa mixture ofdiastereomers which are present in equal concentrations. This sample is defined as a racemicmixture. - Correct answerfalse lactose intoleranceis a medicalcondition that is defined asthe inability to digestlactose (which is found in milk products) due to the lack of the enzyme - Correct answertrue 4. Essentialfattyacids cannot be synthesized by the body and hence must be acquired from the diet. Non-essentialfattyacids can be synthesized by the body. - Correct answertrue 15. Olive oil is an example of an unsaturatedfat and exists as a liquid at room temperature, whereas butter is an example of a saturatedfat and it exists as a solid at room temperature. - Correct answertrue ) Starch is composed of two polysaccharides. The linear starch polysaccharide is known as ____amylose_____ and the branched starch polysaccharide is known as __amylopectin__. b) The major glucose storage carbohydrate in animals is ___glycogen___.c) ___Cellulose____is a polysaccharide found in plants andis indigestible by humans.d) All monosaccharides and disaccharides are reducing sugars except ___sucrose____. - Correct answer What portion of an enzyme is in direct contact with the substrate? - Correct answere) The active site 2. What term describes the pH atwhich an enzyme functions best? - Correct answerb) OptimumpH 3. When the enzymeslightlychanges its shape to bind to a substrate, this is the definition of: - Correct answerc) Induced fit model What is the first step in an enzyme-catalyzed reaction? - Correct answere) Formation of an enzyme-substrate complex 5. The rate of an enzyme-catalyzed reaction initially increases with an increase in the substrate concentration, but eventually reaches a maximum value, even though the concentration of substrate continues to increase. Which of the following best explains why? - Correct answerb) As substrate concentration increases, the active sites of all the enzyme molecules become occupied with substrate molecules, and no additional binding can occur. 6.Which of the following correctly matches the amino acid with its three-letter abbreviation? - Correct answerCysteine: cys . What changes occur in the structure of a protein molecule when it becomes denatured? - Correct answerd)Answers (b) and (c) are correct How is the following amino acid categorized? The structure shows its form at pH = 7. - Correct answerd) Hydrophobic 9. How many oxygen molecules can one hemoglobin molecule bindto? - Correct answerd)4 10. Which of the following correctly describes pepsinogen? - Correct answera) It is the inactive form of the enzyme pepsin 11. What class of enzymes catalyzes the following reaction? - Correct answerc) Hydrolase 12.A second binding site on an allosteric enzymehas the ability to bind to a molecule that alters the shape of the active site. What is this second site called? - Correct answerb) Effector binding site 13.Cooking can be considered an example of protein denaturation by high temperatures. - Correct answertrue An amino acid is considered chiral if its carbon is bonded to four different groups. - Correct answertrue 15. Vitamin B12is an example of a coenzyme and is required by some enzymes to function properly. - Correct answera) True 16. An enzyme speeds up a reaction by increasing its activation energy. - Correct answerfalse read chapter 5 - Correct answer 1. What is meant by the term catabolism - Correct answerc)The biosynthesis (buildup) of molecules with an accompanying intakeof energy d)The degradation (breakdown) of molecules with an accompanying release of energy 2. Catabolism (or catabolic reactions) can be divided into three stages. What occurs in Stage II of catabolism? - Correct answere) The products of food digestion are converted to acetyl CoA Which statement concerning glycolysis is FALSE? - Correct answere)Glycolysis is a process that produces a net yield of 4 ATP molecules per glucose 4. What do the coenzymes NADH and FADH2 carry? - Correct answerb)Electrons 5. What compound is produced during strenuous exercise, when the muscles are depleted of oxygen? - Correct answerd)Lactate 6. Which of the following hormones increases blood glucose levels by stimulatingthe breakdown of glycogen and the production of glucose? - Correct answera) Glucagon 7. The end product of glycolysis is pyruvate. What condition(s)inside the cell is needed to convert pyruvate to acetyl CoA for entry into the citric acid cycle? - Correct answera) Sufficient oxygen 8. How many roundsof the citric acid cycleare required to completely metabolize one glucose molecule? - Correct answer2 9. What alternative name of the citric acid cycleis used in honourof the scientist who first proposed the steps of the cycle? - Correct answerc) Krebs cycle 10.In the first step of the citric acid cycle, acetyl CoA combines withoxaloacetateto form _____________ which is a ____________compound. - Correct answera) Citric acid, six-carbon 11.What is the net yield of ATP per one glucose molecule that undergoes aerobic respiration? - Correct answere)38 12.The last step of Electron Transport Chain is the oxidative phosphorylation,which in fact is the process by which most of the ATP is made. This step requires energy. What is the source of energy for the synthesis of ATPin the cell? - Correct answerc)H+ions flowing through ATP synthase 13. Excess glucose is stored in the body as glycogen. Where are these glycogen reserves primarily found? - Correct answerLiver and skeletal muscles 14. What is the usual fate of the -amino group in the degradationof amino acids? - Correct answerd)It is converted into urea, which is excreted by the body in urine 15.In Electron Transport Chain, amolecule of FADH2is capable of producing 3 molecules of ATP, while a molecule of NADH is capable of producing 2 molecules of ATP. - Correct answerfalse