Tag Archives: delta

How do i prepare for airborne school?

Posted on May 3, 2012 by admin| 1 Comment

Me and my cousin are going to join the army and hopefully make it to delta (fingers crossed). The presrequisits, i believe include being certified as airborne. I’ve never liked the feeling of adrenaline ex: rollor coasters really arent my thing. Water slides dont really bother me though.

I read that you have to be able to run a distance in however much time so i started to run 2 miles a day on my tread mill at home.
THE QUESTION:
What else can i do to get in peek physical condition?
How can i overcome my fear of adrenaline?

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Tagged Adrenaline, airborne school, arent, army, cousin, delta, feeling, fingers, rollor, rollor coasters, SCHOOL, thing, water, water slides

Free Energy vs. Rate?

Posted on April 27, 2012 by admin| 1 Comment

I know that spontaneity (negative free energy. negative delta G) do not necessarily mean that the rate is fast. But if the negative delta G value is large, thus, K is large, can you assume the process is fast? Why or why not?

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Posted in Solar Power

Tagged delta, energy, free, negative free energy, process, rate, spontaneity, value

How can I convert a 3 phase 415 Volt delta induction motor to 3 phase 240 Volts delta?

Posted on February 7, 2011 by admin| 10 Comments

This is a pico hydro power system. The motor output is 4.5 kW.

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Tagged delta, hydro, hydro power, induction, induction motor, motor, phase, pico, pico hydro, power, system, volt, volt delta, volts

Free energy and equilibrium constant K?

Posted on June 3, 2010 by admin| 1 Comment

I am confused about why delta G (DG) = 0 when a system is at equilibrium. I know DG=0 because of the equation DG = -RTlnK and K=1. However, I thought K is a constant that is specific to any reaction, and when something is in equilibrium Q=K, and K doesn’t have to be 1 (in fact, K usually is never 1, but instead, something very small or big, like 6×10^-5 or 7×10^2). So, if a reaction is at equilibrium (a reaction with an eq. constant K that is NOT equal to 1), then DG will not equal to 0. If this is true, then I don’t understand why the textbook tells me DG = 0 when the system is at equilibrium, with K = 1. (I don’t understand why K has to be 1 at equilibrium, since K is a constant that can be any number) Please explain. Thanks.

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Posted in Solar Power

Tagged delta, dg, energy, eq, equation, equilibrium, fact, free energy, NOT, reaction, RTlnK, something, system, textbook

Tabulated values of chemical thermodynamic properties seem inconsistent. What am I misunderstanding?

Posted on May 30, 2010 by admin| 1 Comment

The table in the back of my wife’s chemistry textbook tabulates values of the standard enthalpy of formation delta-Hf0, the standard entropy S0, and the standard free energy of formation delta-Gf0, for a wide variety of elements and compounds, all evaluated at 25C. As I understand it, they should be connected by the relationship

delta-Gf0 = delta-Hf0 – T*S0

They aren’t. For instance, for liquid water, it gave

delta-Hf0 = -286 kJ/mole
S0 = 69.96 J/(mole K)
delta-Gf0 = -237.2 kJ/mole

25C corresponds to T = 298.16 K , so by my calculations detla-Gf0 should be

-286 kJ/mole – 298.16 K * (69.96 J/(mole K) / 1000 (kJ/J)) = -307 kJ/mole

None of the entries in the table work out as I expected, which rules out a typo. I’ve checked with other sources, and they all agree tolerably well with the values tabulated in this textbook. What am I misunderstanding?

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Posted in Solar Power

Tagged 25c, back, C. As, chemical, chemical thermodynamic properties, chemistry, chemistry textbook, delta, elements and compounds, enthalpy, entropy, formation, free energy, relationship, s0, standard enthalpy of formation, table, Tabulated, textbook, wife

Chemistry: Equilibrium Questions?

Posted on May 4, 2010 by admin| 1 Comment

Calculate the equilibrium constant for the following reaction at 80 degrees Celcius. Also, Delta G(final (not)), the standard free energy of formation for Ni(CO)4 (g) = -587.4 kJ/mol. Assume that Delta G (final (not)) is temperature independent.

Ni(s) + 4CO (g) —> <—– Ni(CO)4 (g)

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Posted in Solar Power

Tagged Calculate, celcius, chemistry, degrees celcius, delta, energy, equilibrium, formation, free energy, kj, mol, reaction, Temperature