CHEM 1111 F24_Ans Review Questions PDF

Review questions. Measurement of Mass, Volume and Density 1\. Calculate the density of mercury if 1.00 ✕ 10^2^ g occupies a volume of 7.36 cm^3^. a. 13.587 g/cm^3^ b. 7.36 g/cm^3^ c. 13.6 g/cm^3^ d. 13.5869565 g/cm^3^ 3\. Express the answers to the following calculations using the correct...

Review questions. Measurement of Mass, Volume and Density 1\. Calculate the density of mercury if 1.00 ✕ 10^2^ g occupies a volume of 7.36 cm^3^. a. 13.587 g/cm^3^ b. 7.36 g/cm^3^ c. 13.6 g/cm^3^ d. 13.5869565 g/cm^3^ 3\. Express the answers to the following calculations using the correct number of significant figures. 0.0032 × 273 =  a. 0.8736 b. 0.874 c. 0.90 d. 0.87 4\. How would the darts be positioned on the target for the case of "good accuracy, poor precision"? A B C D a. Scenario B b. Scenario C c. Scenario D d. Scenario A 5\. Choose the correct option regarding Lab: Determining formula of hydrate: 'Weighing to constant mass' a. Was used to calibrate the weighing balance b. Was needed to calibrate the crucible and lid c. Was achieved by making sure that successive weight measurements of the anhydrate were very close to each other d. Was obtained by heating the empty crucible twice and determining the average mass 6\. Which statement depicts the accurate color changes for hydrates and anhydrates a. CoCl~2~.4H~2~O (pink) to CoCl~2~ (white) b. CoCl~2~ (pink) to CoCl~2~.6H~2~O (purple) c. CuSO~4~.5H~2~O (blue) to CuSO~4~ (gray) d. CuSO~4~ (blue) to CuSO~4~.5H~2~O (gray) 7\. If there are three moles of H~2~O for every one mole of LiClO~4~, then what is the hydrate formula? a. LiClO~4~·3H~2~O. b. 3LiClO~4~·3H~2~O c. LiClO~4~·(H~2~O)~3~ d. 3(LiClO~4~)·3H~2~O 8\. A 5.018 gram sample of a certain hydrate of magnesium sulfate, MgSO~4~ xH~2~O, is heated until all the water is driven off. The resulting anhydrous compound weighs 2.449 grams. How many moles of water does the hydrate contain? (Atomic weight: Mg: 24.305 g/mol, S: 32.065 g/mol, O: 15.9994 g/mol, H: 1.0079 g/mol) 9\. For copper recovery experiment, for step 1, what was observed after addition of copper to 6M HNO~3~ ? 10\. In copper recovery experiment, a group of students collected the following experimental data: mass of empty container (for weighing the copper): 34.9007g, mass of container with copper inside: 35.1754g, mass of empty container (for weighing zinc): 29.1775g, mass of container & zinc: 30.6775g, mass of watch glass: 29.1773g, mass of watch glass + filter paper: 29.2809g, mass of watch glass + filter paper + final recovered Cu product: 29.5159g, calculate the recovery yield of copper? a. 99.21% b. 85.55% c. 100.8% d. 18.31% 11\. In the copper recovery experiment, the last reaction step is shown below. Which of the following statements best describes this reaction. CuSO~4~(*aq*) + Zn(*s*) → Cu(*s*) + ZnSO~4~(*aq*) a. Copper is oxidized and Zinc is reduced b. Sulfur is oxidized and Zinc is reduced c. Zinc is oxidized and sulfur is reduced. d. Copper is reduced and Zinc is oxidized 12\. Identify the type of reaction: Cu(NO~3~)~2~(*aq*) + 2NaOH(*aq*) → Cu(OH)~2~(*s*) + 2NaNO~3~(*aq*) 13\. In the experiment of separating oleic acid, iron, sand, salt and zinc oxide, the first step is to remove oleic acid with propanol, this is because: a. Among the mixture, only oleic acid is an organic compound and soluble in propanol. b. Salt is soluble in oleic acid c. Iron can be pulled out by a bar magnet d. Water should be used first since it is a universal solvent 14\. Experimentally, you can separate two liquids from each other by: a. Distillation b. Evaporation c. Decantation d. Recrystallization 15\. All the following methods are used to separate a solid from a liquid, except: a. Filtration b. Decantation c. Evaporation d. Distillation 16\. What piece of equipment can be used to separate solvent from oleic acid? a. Rubber policeman b. Gravity filtration c. Hot plate d. Infrared spectroscopy 17\. The equivalence point of the acid/base titration between HCl and NaOH occurred when: A. the acid and the base neutralized each other B. when the solution turned a faint pink color C. the moles of H^+^ = the moles of OH^-^ a. Only A and C are correct b. Only A and B are correct c. A, B and C are correct 18\. A group of students conducted an acid/base titration of 24.35 mL of 0.3502 M HCl, at the end point, the total volume of NaOH used was 36.44 mL. For this experiment, the moles of HCl at the end point a. 0.234 moles HCl b. 0.14 moles HCl c. 0.0096 moles HCl d. 0.0085 moles HCl e. **None of the above are correct** 19\. What was the visual indicator for end point for Acid-base titration experiment? Explain the color change for phenolphthalein. 20\. The equivalence point in a titration of 20.0 mL of HCl with 0.500 M NaOH was determined to be at 13.5 mL. What is true about the resulting solution? a. The molarity of HCl is 0.337 M b. The number of moles of NaOH at equivalence point are 0.00675 and molarity of HCl is 0.3 M c. The molarity of HCl is 0.5 M d. The molarity of HCl is 0.337 M and number of moles of NaOH at equivalence point are 0.00675 21\. If a gas\'s Kelvin temperature doubles and its volume remains constant, then what happens to its pressure? a. It is halved. b. It remains the same. c. It doubles. d. It quadruples. e. None of the above 22\. Which of the following pairs of variables are inversely proportional for an ideal gas, if all other variables are kept constant. a. I only. b. II only c. I and II only d. I and III only e. I, II, and III 23\. According to the Ideal Gas Law, what are the units for the gas constant R? a. volume⋅pressure/(moles⋅Kelvin) b. volume⋅Kelvin/(moles⋅pressure) c. volume⋅moles/(Kelvin⋅pressure) d. volume⋅moles⋅pressure/Kelvin e. volume⋅moles⋅Kelvin/pressure 24\. How was hydrogen gas generated in our lab experiment on gases (Part II)? a. Electrolysis of H~2~O b. Reaction of Mg with HCl c. Reaction of Mg with H~2~O d. From a cylinder filled with H~2~ 25\. Given that the specific heat capacity of water is 4.2 J/(g°C), the heat capacity of 80 g of water in J/°C is a. 672 b. 320 c. 336 d. 168 26\. If 2016 J of heat are gained by 70 g of oil \[having a specific heat capacity of 2.4 J/(g°C)\], the temperature change in the oil is a. 7 °C b. 168 °C c. 84 °C d. 12 °C 27\. What was the reason behind using cold water for energy content of foods and fuels experiment? 28\. Recall sources of error for energy content of food experiment. Explain in complete sentences, include ways to minimize or mitigate these errors. 29\. In the oxidation-reduction reaction below Zn + HCl =\> ZnCl~2~ + H~2~ a. Cl is oxidized and Zn is reduced. b. H is both oxidized and reduced. c. Zn is oxidized and H is reduced d. Zn is both oxidized and reduced. 30\. A displacement reaction will occur when\... a. A less reactive metal displaces a more reactive metal from its compound b. Displacement only occurs when two of the same metals are reacted c. Displacement reactions will only occur in metals above Iron (Fe) in the reactivity series d. a more reactive metal displaces a less reactive metal from its compound. 31\. The reaction between Ca + Zn(NO~3~)~2~ leads to: a. Ca + Zn(NO~3~)~2~ b. Zn + Ca(NO~3~)~2~ c. there will be no reaction d. Zn + CaNO~3~ 32\. What is the product of a reaction between Magnesium metal and hydrochloric acid? a. magnesium nitrate and hydrogen gas b. magnesium sulfate and hydrogen gas c. magnesium oxide and oxygen gas d. magnesium chloride and hydrogen gas 33\. Which of the following could the flame test be used for? a. To identify metal cations b. To identify alkene reactions c. To identify metal anions d. To identify salt precipitates 34\. Which of the following explains why different metals produce different colors during the flame test? a. Each metal was isolated from a different place b. Each metal has a unique electron configuration c. Each metal has a unique salt bond d. Each metal has a unique number of extra electrons 35\. A student performs a flame test on an unknown substance and observes a blue green flame. Which substance is s/he most likely using? a. Copper b. Lithium c. Calcium d. Potassium 36\. Which portion of the visible spectrum has a longer wavelength? a. orange b. Green c. Red d. blue 37\. Which of the following is a strong electrolyte? a. Mixture of Al and water b. Mixture of NaCl and water c. Mixture of SiO~2~ and water d. Mixture of sugar and water 38\. Which statement is correct about a strong electrolyte? a. Examples of strong electrolytes include CH~3~CO~2~H and Na\[CH~3~CO~2~\] b. It conducts electricity because its ions are fixed in place c. It conducts electricity because its ions can move in response to electrical forces d. It is partially ionized in aqueous solution. 39\. The pH of chicken soup is 5.80. Which of the following statements apply to chicken soup? a. [\$\\frac{\\lbrack{H\_{3}O}\^{+}\\rbrack}{\\lbrack OH\^{-}\\rbrack} \> 1\$]{.math.inline} b. [\$\\frac{\\lbrack{H\_{3}O}\^{+}\\rbrack}{\\lbrack OH\^{-}\\rbrack} \< 1\$]{.math.inline} c. [\$\\frac{\\lbrack{H\_{3}O}\^{+}\\rbrack}{\\lbrack OH\^{-}\\rbrack} = 1\$]{.math.inline} d. [\$\\frac{\\lbrack OH\^{-}\\rbrack}{\\lbrack{H\_{3}O}\^{+}\\rbrack} \> 1\$]{.math.inline} 40\. Recall the sources of error for pH and conductivity experiment, write your best recollection of those errors here: 41\. Choose the molecule that is incorrectly matched with the electronic geometry about the central atom (note: this is for electronic geometry, not molecular geometry, the latter does not count the lone-pair electron group). a. CF~4~ - tetrahedral b. BeBr~2~ - linear c. H~2~O - tetrahedral d. NH~3~ - tetrahedral e. PF~3~ -- pyramidal 42\. Which of the following four molecules are polar: BH~3,~ OF~2,~ CS~2~, PF~5~? a. all except PF~5~ b. only OF~2~ c. only BH~3~ and OF~2~ d. none of these e. all of these 43\. Which of the following pairs of molecules and their molecular geometries is INCORRECT? a. H~2~O - bent b. BF~3~ - trigonal planar c. NF~3~ - trigonal planar d. AsF~5~ - trigonal bipyramidal e. SeF~6~ -- octahedral 44\. Which molecule has a linear arrangement? a. CH~4~ b. H~2~O c. CO~2~ d. NH~3~ e. BF~3~ 45\. What is the correct method to prepare 500 mL of 0.5 M HCl solution a. Add distilled water to concentrated acid in a graduated cylinder b. Water and acid can be added in either order c. Add concentrated acid to distilled water in a graduated cylinder d. Not enough information to answer the question 46\. Which of the following is the most accurate device for measuring 50 mL water: a. 125 mL Erlenmeyer flask b. 50 mL graduated cylinder c. 100 mL beaker d. 50 mL beaker 47\. How would you clean up an acid spill: 48\. (4 points) At what temperature will 41.6 grams N~2~ exert a pressure of 815 torr in a 20.0 L cylinder? (Hint: atomic weight of N is 14.06 g/mol, 1 atm = 760 torr, R = 0.08205 L·atm/mol [ ]{.math.inline}K) a. 134 K b. 177 K c. 238 K d. 337 K e. 400 K 49\. What was your favorite experiment this semester and why.