Sorting actions by energy level required, etc.

How about sorting actions not only by context,
but also by level of energy required?

I’m experiencing a further boost in feelings
of freedom, overall energy and motivation as
I implement the modifications I describe here
to David Allen’s “Getting Things Done” (GTD)

One of Allen’s highly effective, though wonderfully
simple, innovations is to sort actions by context,
so that when you’re deciding what to do right
now, you can present yourself with a list of
useful actions that are doable in the place where
you are right now (at home, at work, on the computer,
out shopping, etc.)

Now I’m starting to further subdivide my action
lists by amount of time required and by level of
mental or physical energy required, so that I can
now present myself with a list of actions every
one of which is not only doable in the context
I’m in, but is also actually and practically doable
here and now, with the amount of time and energy
I have available right now.

I have two ways of implementing this: one on paper
and one on the computer. They’re pretty much
mathematically equivalent, and allow me to quickly
and easily find a list of actions doable within
the current context, time and energy, and further
sorted in order of priority, energy and time.

One of the fantastic things about GTD’s sorting by
context is that it greatly cuts down on how often
you have the frustrating thought, “I can’t do
that right now”. I was marvelling about this and
asked myself what other wonderful but simple ideas
nobody has thought of yet. This time something
sprang to mind: why not pre-sort by time, energy
and priority as well as by context?

I don’t know whether this has been done by others
already. I know there’s lots of GTD software
out there, but a Google search for
‘GTD software “sorted by energy”‘
didn’t turn up anything.

My understanding of GTD is that usually, if the list
for a context is short enough, maybe 10 or 20 actions,
then you read the whole list each time, first
selecting by time, then by energy, and finally sorting
by priority.

Well, for one thing, my lists aren’t just 10 or 20 items.

Now when I first add an action to a list, I assign
it a time, energy and priority. One advantage of
this is that, like Allen’s sorting by context, it
helps force me to clarify the action as a single,
specific physical action; especially when I consider
energy, which involves imagining myself actually
doing it. Once I’ve gone through those couple of
seconds of hard thinking, actually doing the action
can be like coasting downhill.

The time represents how much time I need available in
order to feel comfortable starting on an action. I’m predicting
how I’ll feel when I start, not the end result. It could
be longer or shorter than the length of time I think the
action will take, depending on how open I am to interrupting
that particular action. I like having a list of quick actions so
I don’t have to read over a longer list and regretfully reject a lot of actions
I wish I had time for.

I have a separate page for each amount of time
(quick, 5-minute, 15-minute, 1-hour and 5-hour).
The higher the priority, the further to the left
on the page I start writing it.
Vertical position on the page indicates a gradation
of energy from high-energy at the top to easy at
the bottom. If I’m not at my top energy level, I
cover up a top section of the page when I review it.

In this way, once I’m displaying the doables, those
which will catch my eye first are those with the
highest priority, highest energy and longest time
required. On the computer, I display them sorted
by priority, then by energy level (highest energy
required first), then by time. At home, where long
chunks of time seem rarer, I’m doing the longest-time
doables first, while at work I sort them the other
way to get the quicker items cleared off the list.

Rather than repeating the discouraging question,
“Do I have the energy to do this right now?”, I’m
asking myself, at different times, the energy-boosting
questions “How much energy will I need to do this?”
(from 1 to 9) and “What energy level am I at right
now?” Addressing the highest-energy doables first also
encourages an “I can do it!” attitude, and leaves
a downhill ride for the remaining actions.

Also by Cathy Woodgold:

book review of “Getting Things Done”

Time Management

Home page

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Electrolysis of water, explained

I had never found a satisfactory explanation anywhere
for how electrolysis of water works, so finally, with the
help of a friend, I figured it out, and explain it here.

Electrolysis of water is when you stick two electrodes
into a container of water, apply electricity, and get
hydrogen gas and oxygen gas bubbling out.

The standard explanations on the Internet and in chemistry
textbooks, which I find unsatisfactorily incomplete,
go something like this:

When attempting electrolysis with plain water, it doesn’t
work very well.  The concentrations of H+ and of OH- in
pure water are very low, so there is very little migration
of ions when an electric field is applied.  OH- accumulates
near the cathode, and H+ near the anode, making those
parts of the solution electrically charged, so that it
starts to take very high voltages to push electric
current through.  After the first few bubbles, the
reaction slows down to a snail’s pace.  However, adding
salt to the water makes the water easily conduct
electricity by movement of salt ions, and the electrolysis
reaction easily continues.

I can see how adding salt makes the water conductive,
but what I didn’t get about this was: how does that help
divide H2O into H2 and O2?  I mean, you could short-circuit
the electrodes by joining them with a piece of wire.
That would allow electricity to flow between them, but
it wouldn’t split water molecules.  What exactly is it
about the movement of salt ions that facilitates electrolysis?

There are two mechanisms.  Mechanism I, which begins in
full force as soon as the electricity is applied, involves
progressively changing concentrations of ions.  Gradually,
Mechanism II takes over, which can continue in a steady
state — steady except for the continual bubbling away
of oxygen and hydrogen and resultant reduction in volume
of water, which I ignore here.

Mechanism I works like this: positive salt ions approach
the cathode and remain there, producing an ever-increasing
concentration of these ions very close to the cathode.
Similarly, negative salt ions accumulate close to the anode.
These are accompanied by an ever-increasing concentration
of OH- near the cathode and of H+ near the anode, making
the solution approximately electrically neutral, although
alkaline near the cathode and acidic near the anode.

The OH- is formed at the cathode when electrons are added
to the water and H2 bubbles away:

2H2O + 2e- –> 2OH- + H2

The H+ is formed at the anode when electrons are removed
from the water and O2 bubbles away:

2H2O –> O2 + 4H+ + 4e-

But Mechanism I can’t go on forever.  It requires
continually increasing concentrations.  Eventually
something’s going to go bust.  Besides, people have
run electrolysis experiments for days, bubbling away
as hydrogen and oxygen half or more of the volume
of water.  There aren’t enough salt ions in the
solution to electrolise that much water via Mechanism I.
It has been argued that the salt ions diffuse back
and are recycled to participate in Mechanism I again;
however, although diffusion does occur, this can’t
explain the continuing reaction: moving in the opposite
direction would be undoing their work, cancelling the
effect and reducing the rate of electrolysis.

No, another mechanism is needed.  Luckily, once those
ion concentrations reach significant levels, something
wonderful happens:  it is no longer true that the
concentrations of H+ and of OH- are too low to support
much ion movement.  No, their concentrations become
considerable, and their migration becomes a significant
factor in the continuing electrolysis reaction.

After Mechanism I has been going for a while and some
diffusion has occurred, we have alkaline solution near
the cathode, gradually gradating to reduced alkalinity
further from the cathode, neutral in a 2-dimensional zone
(surface) perhaps halfway between the electrodes, and
gradually increasing acidity towards the anode.  When
Mechanism II is the only thing happening, these
concentrations are not changing with time.

In the alkaline zone, because there is a gradient in
the concentration of positive salt ions, there ions
have a tendency to diffuse away from the cathode.
Once steady state is reached, this tendency is exactly
balanced by the tendency to migrate towards the cathode
due to the applied electricity.

The numerous OH- ions in the alkaline zone have the same
tendency to diffuse away from the cathode that the
positive salt ions have, because they have approximately
the same concentrations and gradients of concentration.
However, their electric charge is the opposite, which
means that their push to migrate due to the electricity
is also away from the cathode, not the opposite direction
as is the case with the salt ions.  It’s like when your
salary and your sense of moral duty are both pushing
you to perform the same actions.

So, throughout the alkaline part of the solution, we have
significant migration of OH- away from the cathode.
Similarly, H+ is migrating away from the anode throughout
the acidic part of the solution.  The role of the salt
ions is to cancel electric charge: in Mechanism I
so that the concentrations of H+ and OH- can increase,
and in Mechanism II so that their concentrations can
remain high, allowing migration to occur.

Since there is ion migration without changes in
concentrations, there must be a source and a sink for
each of these ions.  The OH- are generated at the cathode
and the H+ at the anode in the reactions described above;
and these two types of ions disappear when they meet
in the middle and join to form H2O.  They must join,
in almost all cases, because you can’t have high
concentrations of both these ions in the same part
of an aqueous solution.

In effect, in order to split one water molecule, there
are three reactions:  one water molecule splits at the
cathode, and part of it contributes to the production
of H2.  Another water molecule splits at the anode,
and part of it contributes to the production of O2.
The two remaining parts migrate to the middle of the
solution and join.  These three reactions add up to a
net splitting of one water molecule.  Heat is
given off at the neutral part of the solution, where
the rejoining occurs.

Since concentrations are not changing with time and
there is therefore no accumulation of these ions
anywhere, the total flux of ions has to be the
same at different distances from the cathode, to
carry the same amount of current.  To achieve this,
the velocity of the ions is higher where their
concentration is lower.  The higher velocity must
be caused by a greater electric field.  Therefore,
the voltage drop is larger at and near the surface
where the solution is chemically neutral, (perhaps
midway between the electrodes).  The ions approaching
the neutral surface act like water approaching
a waterfall:  slowly at first, then gradually
speeding up and thinning out until suddenly they’re
rushing off the edge — or into the arms of a
waiting ion of the opposite charge.

Somewhat related links:

Cathy Woodgold’s home page

U.S. Department of Defense report on Cold Fusion

Status of Cold Fusion (2010), Storms, Naturwissenschaften

Thanks to Abd ul-Rahman Lomax for enlightening
discussion, without which &c.

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