mock exam 1 and solutions
mock exam 1 and solutions CEM 142
Popular in Chemistry
Popular in Chemistry
This page Study Guide was uploaded by Elisa Chaparro on Wednesday September 30, 2015. The Study Guide belongs to CEM 142 at Michigan State University taught by Pollock in Summer 2015. Since its upload, it has received 116 views. For similar materials see Chemistry in Chemistry at Michigan State University.
Reviews for mock exam 1 and solutions
These were really helpful...I'll be checking back regularly for these
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 09/30/15
Name ID Section CEM z MOCK EXAM 1 Fall 2015 Mark the best answer on your bubble sheet and on the exam Use this diagram for Q 1 3 5 39 I I I I I I 6 You a human being are what kind of I I system A Open 1 For the process shown AH for the system B Isolated is C Closed A C 0 D It depends on whether you are B D it depends on the temp awake or asleep 2 For the process Shown AS for the SyStem 7 What is the boiling point of methanol if AH 1s for vaporization is 353 kJmol and AS for A C vaporization is 105 B D 1t depends on the temp J mol K A 336 K C 373 K 3 For the process shown AG 13 297 K D 033K K A is always B is always 8 Which of the following would you predict to C becomes mote POSitive as the have the smallest AHvap The heat required temperature 1he1 easee to change one mole of substance from a 13 becomes mote negatlve as the liquid phase to a gas phase vaporize temperature 1ncreases A CH3OH c 012 B CH4 D NaF 4 Which has the highest entropy per mole A H20 s C H20 1 9 If you wanted to prepare 500 mL of a 020M B H20 g D All the same solution of dextrose C6H1206 in water how much dextrose would you need 5 When liquid water freezes below 0 oC A the entropy of the system increases and 3 180g the entropy of the surroundings b 90g increases C 36g B the entropy of the system increases and d 18g the entropy of the surroundings deereaseso 10 How would you prepare the dextrose C the ehtl39epy 0f the SyStem decreases ahd solution that you made in Question 9 the ehtl39epy 0f the Shh39elmdihgs a Put the dextrose in a beaker and add 500 deereases mL of water Do the ehtl39epy 0f the SyStem decreases ahd b Put the dextrose into 05 L volumetric the ehtl epy 0f the Shh ehhdihgs ask and add 500 mL of water increases Name ID CEM z MOCK EXAM 1 Fall 2015 Put the dextrose into 05 L volumetric ask and add water until the volume of the solution is 500 mL Fill a 05L volumetric ask with water and then add in the dextrose 11 Is Ne or Xe more soluble in liquid water and which of the following best explains Why it is the more soluble 12 13 14 a Ne because it is smaller than Xe so it can fit between the water molecules easier which results in stronger interactions Ne because it is similar in size to water so that it can replace water molecules easily due to its polarizablity Xe because it is larger than Ne and the larger the atom the more soluble it is in water Xe because it is more polarizable than Ne resulting in stronger interactions with the water molecules Which compound do you predict would be most soluble in hexane C6H14 a 990quot H20 CH3OH CH3CH20H CH3CH2CH20H It is not possible to predict solubility from the information given Which of the following must be true about a process where the sign of AG is negative a b c d It must be exothermic The entropy of the system must increase The entropy of the universe must increase All are true When calcium nitrate is placed in water the solution becomes clear and the temperature Section increases What are the values of AH AS and AG for this process AH AS AG a b c d 15 Which would be the best solvent for grease 16 17 18 a mixture of hydrocarbons a toluene C7H8 b ammonia NH3 c molten sodium chloride d apple juice Which compounds can form hydrogen bonds with water but not with itself Hint draw out the Lewis structures a CH3OCH3 b CH3CH20H c CH3C02H d none of them form hydrogen bonds A high blood alcohol concentration is considered to be 025 gdL What is the molarity of this blood alcohol CH3CH20H level a 54 x 10 2 M b 54 x 1041 M c 115 M d 115 M Which of these pictures shows a solution of K28 water molecules are omitted for clarity K is shaded and the S is unshaded Name CEM z MOCK EXAM 1 Fall 2015 3 00 pp 0 a b o o o O o 39 00 o c d 19 Rank the following compounds in increasing order of solubility when placed in ammonia NH33 a H20 CH2C12 CH4 b H20 CH4 CH2C12 c CH4 CH2C12 H20 d CH4 H20 CH2C12 20 Which graph shows the change in AG as the temperature increases for a process where AHis andASis A Temperature Temperature a b AG AG Temperature Temperature c d 21 When a solution of CaC12 is dissolved in II water the temperature rises Which of these statements can de nitely be inferred from this observation The entropy change for this process is negative The entropy change for this process is positive Section III IV 22 23 24 The interactions between the species in solution are stronger compared to those in the separate solute and solvent The interactions in the separate solute and solvent are stronger compared to those between the species in solution a I and III b I and IV c II and III d II and IV e III only The entropy change when carbon dioxide C02 g dissolves in water is a Positive because mixing things up always increases the entropy since there are more available positions b Negative because the number of positions available to the carbon dioxide molecules decreases c Zero because carbon dioxide does not dissolve in water d Either positive or negative depending on the temperature Ethanol has a boiling point of 78 C and a melting point of l 14 C What happens when ethanol goes from 84 C to 90 C a the entropy of the system decreases and the entropy of the surroundings decreases b the entropy of the system decreases and the entropy of the surroundings increases c the entropy of the system increases and the entropy of the surroundings increases d the entropy of the system increases and the entropy of the surroundings decreases Consider the following reaction for the synthesis of ammonia Name ID CEM z MOCK EXAM 1 Fall 2015 N2 3 H2 gt 2 NH3 AH 922 kJmol AS 726 JK At 25 C would this reaction be thermodynamically spontaneous a No because AG is positive b No because AG is negative c Yes because AG is positive 25 Why don t oil and water miX a Because oil is nonpolar and water is polar b There are no attractive forces between oil molecules and water molecules therefore the hydrogen bonds between water molecules would require too much energy to break c The entropy of the system is higher in the unmixed state because nonpolar molecules cause water molecules to cluster around them d Oil and water repel each other because they both contain negative polar regions Section 26 Calcium phosphate Ca3PO42 is insoluble 27 in water The AH for solution is about zero Predict the signs of AS and AG AS AG a b c d Which substance is most likely to be absorbed by Febreeze Structure shown here El H2 CH b 32 H2 CH 3 3 H30 C H30 IIC S o H NaCl d all of them Useful information AG AH TAS M R T R 008206 L atm mol391 K391
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'