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M3: Exam - Requires Respondus LockDown
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- Due No due date
- Points 100
- Questions 10
- Time Limit 120 Minutes
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Attempt History
Attempt Time Score LATEST Attempt 1 111 minutes 79 out of 100
Score for this quiz: 79 out of 100
Submitted Jan 12 at 3:28pm This attempt took 111 minutes.
Question 1
10 / 10 pts
You may find the following resources helpful: Scientific Calculator (Links to an external site.) Periodic Table Equation Table
Show the calculation of the new volume of a gas sample which has an original volume of 660 ml when collected at 660 mm and 38oC when the pressure increases to 780 mm and the temperature increases to 45oC. Your Answer: 660/1000 = .66L 38+273 = 311K 45+273 = 318k 660mm/760 = 0.8684210526 atm 780mm/760 = 1.026315789 atm pxv/ t = pxv/ t 0.8684210526 X .66 / 311 = 1.026315789 atm x V / 318 0.5731578947/311 = 1.026315789V/ 0.5731578947 x 318 = 1.026315789V x 311 182.2642105 = 319.1842104 V 0.5710314125 L= v .571 L ~ V
Question 2
10 / 10 pts
You may find the following resources helpful: Scientific Calculator (Links to an external site.) Periodic Table Equation Table
n=0. V = nRT/p v=(0.2778501346)(.0821)(303)/1. v=6.911883303/1. v=5.529506642 L v~5.53 L 2/
Question 4
10 / 10 pts
You may find the following resources helpful: Scientific Calculator (Links to an external site.) Periodic Table Equation Table Show the calculation of the mole fraction of each gas in a 1.00 liter container holding a mixture of 7.60 g of N 2 and 8.40 g of O 2 at 25oC. Your Answer: n2=28.02 n = 7.60/28. n=0. o2=32 mw. n = 8.40/ n=0. 2625 nt= 0. 0.2712348323/0.5337348323 = 0.5081827452 moles N 0.2625/0.5337348323 = 0.4918172548 moles o
nN2 = gN2 / (MWN2) = 7.60 g / 28.02 = 0.2712 mol nO2 = gO2 / (MWO2) = 8.40 g / 32.00 = 0.2625 mol XN2 = 0.2712 / (0.2712 + 0.2625) = 0. 5082 XO2 = 0.2625 / (0.2712 + 0.2625) = 0.
Question 5
10 / 10 pts
You may find the following resources helpful: Scientific Calculator (Links to an external site.) Periodic Table Equation Table Show the calculation of the molecular weight of an unknown gas if the rate of effusion of Neon gas (Ne) is 1.86 times faster than that of an unknown gas. Your Answer: unknown mw = (r^2)(known mw) ne=mw=20. (1.86^2)(20.18) (3.4596)(20.18) unknown mw = 69. (rNe /runknown)^2 = MWunknown / MWNe (1.86/1)^2 = MWunknown / 20. MWunknown = (1.86)^2 x 20.18 = 69.
Question 6
7 / 10 pts
You may find the following resources helpful: Scientific Calculator (Links to an external site.) Periodic Table Equation Table
Periodic Table Equation Table Write the subshell electron configuration (i.e.1s^2 2s^2 , etc.) for the Ti 22 atom and then identify the last electron to fill and write the 4 quantum numbers (n, l, mland ms) for this electron. Your Answer: Ti 22 = 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^2 3d^2 s- 0 p d f *_ *_ _ _ _
- 2 - 1 0 1 2 n=3 I =2 ml=- 1 ms=+1/ Ti 22 = 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^2 : n=3, l=2, ml = - 1, ms = +1/
Question 9
5 / 10 pts
You may find the following resources helpful: Scientific Calculator (Links to an external site.) Periodic Table
Equation Table List and explain your answers for each of the following two problems: 1.) List and explain which of the following atoms holds its valence electrons less tightly. Si or Cl 2.) List and explain which of the following atoms forms a positive ion with more difficulty. B or F Your Answer:
- electronegativity increases vertically and as you go from left to right. Si holds its valence electrons less tightly because Cl electronegativity is higher
- ionization increases vertically and as you go from left to right. so B would have more difficulty because F has a higher ionization according to the periodic table
- Si holds its valence electrons less tightly than Cl since electronegativity increases as you go to the right in a period which means that Si which is further to the left in the period has the lower electronegativity and therefore the lower attraction for its valence electrons.
- F forms a positive ion less easily than B since ionization potential increases as you go to the right in a period which means that F with the higher ionization potential requires more energy to lose an electron and form a positive ion so it does so less easily.
Question 10
0 / 10 pts
You may find the following resources helpful: Scientific Calculator (Links to an external site.)
B.
Quiz Score:
