CSU CHEMISTRY 103 MIDTERM EXAM 2025

CSU CHEMISTRY 103 MIDTERM EXAM 2025 The charge on a neutron is a) -1 b) 0 c) +1 d) it depends on the atom - Correct Ans-b) 0 what is the shape around the atom pointed to be the arrow labeled C? PHOTO a) linear b) bent c) trigonal Pyramid d) trigonal planar e) tetrahedral - Correct Ans-e) tetrahedral The molecule shown is PHOTO a) a fat b) a fatty acid c) a sugar or carbohydrate d) a carboxylic acid e) an aromatic compound - Correct Ans-a) a fat which of the following statements is tru about the term "essential" when referring to essential fatty acids? a) life cannot occur without these substances b) humans cannot synthesize these substances so they must be included in the diet c) these substances cannot be synthesized in the laboratory d) plant protein sources do not contain these substances e) these are what is left when all the extra parts of fats and proteins are taken away; they are the fundamental building block of those biomolecules - Correct Ans-b) humans cannot synthesize these substances so they must be included in the diet the correctly drawn structure of C2H2 has a) only single bonds b) a double bond c) a triple bond d) a lone pair e) more than one of A-D - Correct Ans-c) a triple bond the structure of D-glyceraldehyde is shown... what is the mirror image? PHOTOS - Correct Ans-C CSU CHEM 103 CSU CHEM 103 what is the monomer that makes up the polymer in wool? a) an amino acid b) glucose c) a nucleotide d) ethylene e) starch - Correct Ans-a) an amino acid The bond shown in the triangle is called a(n) __________ bond a) ester b) acid c) amine d) peptide e) alcohol - Correct Ans-d) peptide A cup of gasoline is about 250 mL. When ignited this amount of gasoline explodes into a fireball. (glass containers around this size are used as grenades in street riots) if a snickers bar has 250 kcal when burned. how many Snickers bars equivalents is 250 mL of gasoline? the density of gasoline is 0.75 g/mL a) 1-5 b) 5-10 c) 10-20 d) 20-50 e) more than 50 - Correct Ans-b) 5-10 You have a car that runs on hydrogen (H2). the hydrogen tanks in this car can hold 5000 g. How much energy (in GJ) is produced by burning 5000 g of H2? a) 1 b) 1-2 c) 2-10 d) 10-50 e) 50 - Correct Ans-a) 1 How many different amino acids are there in naturally occurring proteins? a) 11 b) 20 c) 64 d) 1000 e) unlimited - Correct Ans-b) 20 Biofuels/ biomass make up what percentage of renewables? Don't count nuclear as a renewable a) less than 10% b) 10-25% c) 25-40% d) 40-60% e) More than 60% - Correct Ans-c) 25-40% CSU CHEM 103 CSU CHEM 103 in a nuclear fission reaction _______ is converted into energy a) hydrogen b) lithium c) matter d) water e) light - Correct Ans-C) matter Use the bond energy table on the cover page o calculate the energy change associated with the combustion of propane : CH3CH2CH3+502---- 3(O2+4H2O notice that the O2 bond is a double bond and the CO bonds in Co2 are double bonds a) between - 10,000 and -4000 KJ/mole b) between -4000 and -2000 KJ/mol c) between -2000 and 0 KJ/mol d) between 0 and +2000 KJ/mol e) between +2000 and +10,000 KJ/mol - Correct Ans-b) between -4000 and -2000 KJ/mol for a chemical equation which of the following does NOT need to remain the same when comparing all of the reactions to all of the products? a) the masses b) the number of molecules c) the types/identities of atoms d) the number of atoms - Correct Ans-b) the number of molecules Draw the lewis structure for acetylene (C2H2) what is the bond energy for the carbon carbon bond in acetylene a) 356 KJ/mol b) 416 KJ/mol c) 598 KJ/mol d) 813 KJ/mol e) 249 KJ/mol - Correct Ans-d) 813 KJ/mol