Sage Of The Arctic

Stephanie Dalquist, Sam Kendig

HINTS:
• Stuck on a problem: This is a celebration of learning, so you shouldn't need to know anything more than 3.09fun to solve any of these.
• Stuck on letters ⇒ elements: You're having a hard time? "No shit, Sherlock." "Keep digging, Watson. It's all elementary"
CLUES IN PUZZLE:
• Celebration of learning = 3.091 quiz
• HTML names of each puzzle page indicate that you have to solve them all, and they're all integer values
• It's elementary = convert integer answers to chemical elements
SOLUTION:
1. Solve chemistry problems
2. Use numbers as answers to get chemistry symbols (11 is Na, e.g.)
DETAILED SOLUTIONS:

ACID EATERS: He

```  Acid dissociation equilibrium problem.  Ka=1.76E-5,  concentration = 5.69 M, Ka=[H+][Ac]/[HAc].
Species  [ ]o  change[ ]  equilibrium [ ]
HAc      5.69  -x         5.69-x
H+       0     +x         +x
Ac-      0     +x         +x
x ends up being 0.01, so the pH of the solution is 2, or Helium.
```

PUMP UP THE VOLUME: Ra

```  PV=nRT.  nR*(T1/P1 - T2/P2)=13.80 mol*0.08206Latm/molK*(273K/1atm-293K/1.5atm)=deltaV= 88L
```

IRON MAIDEN: S

```  The reaction being cued is thermite, 2Al(s)+Fe2O3(s) -> Al2O3(s)+2Fe(s)
3835.2 grams Fe2O3 = 24 moles, 446.4 g Al = 16 moles.  16 moles of
Aluminum will be used, so 8 moles of Fe2O3 will be used,
and 16 moles will be left over.
```

MEN AT WORK: He

```  Thermo, cycles, ideal gas.  Keep in mind it's adiabatic.  w=-2.03 MJ
on gas or 2 by gas, so 2, or He.
```

```  This can be solved from the combustion functions and deltaH's, which can be looked up:
Cgraphite(s)+O2(g) -> CO2(g)  deltaH=-393.5kJ
Cdiamond(s)+O2(g) -> CO2(g)   deltaH=-395.4kJ
Hess' Law:
Cgraphite(s)+O2(g) -> COs(g)            deltaH=-393.5kJ
CO2(g)             -> Cdiamond(s)+O2(g) deltaH=-(-395.4)kJ
Cgraphite(s)       -> Cdiamond(s)       deltaH=1.9kJ PER MOLE
The problem is for 335 grams, or 27.85 moles.  Energy required is 53 kilojoules.
```

```  The compound is triphenylmethyl and there are ten resonance
structures, e.g. 9 more than the one shown.
```

VAPOR TRAILS: Er

```  This is a Clausius-Clayperon problem: ln(P2/P1)=deltaHvap/R*(1/T2-1/T1)
ln(23.8/x)=(43900 J/mol)/(8.3145 J/Kmol)(1/316.77-1/298) Pressure = 68 torr.
```

AS AN ASIDE:

The names of the puzzles are not part of the solution, but are thematic to the chemistry problem. They are:

• Acid Eaters (Ramones album)
• Pump up the Volume (Soundtrack and song)
• Iron Maiden (band)
• Men at Work (band known for "Land Down Under")